diff --git a/contracts/extension/Staking1155.sol b/contracts/extension/Staking1155.sol
index 385b31721..661ba0f1f 100644
--- a/contracts/extension/Staking1155.sol
+++ b/contracts/extension/Staking1155.sol
@@ -110,6 +110,8 @@ abstract contract Staking1155 is ReentrancyGuard, IStaking1155 {
         StakingCondition memory condition = _nextConditionId == 0
             ? defaultCondition[nextDefaultConditionId - 1]
             : stakingConditions[_tokenId][_nextConditionId - 1];
+        require(_timeUnit != condition.timeUnit, "Time-unit unchanged.");
+
         _setStakingCondition(_tokenId, _timeUnit, condition.rewardsPerUnitTime);
 
         emit UpdatedTimeUnit(_tokenId, condition.timeUnit, _timeUnit);
@@ -134,6 +136,8 @@ abstract contract Staking1155 is ReentrancyGuard, IStaking1155 {
         StakingCondition memory condition = _nextConditionId == 0
             ? defaultCondition[nextDefaultConditionId - 1]
             : stakingConditions[_tokenId][_nextConditionId - 1];
+        require(_rewardsPerUnitTime != condition.rewardsPerUnitTime, "Reward unchanged.");
+
         _setStakingCondition(_tokenId, condition.timeUnit, _rewardsPerUnitTime);
 
         emit UpdatedRewardsPerUnitTime(_tokenId, condition.rewardsPerUnitTime, _rewardsPerUnitTime);
@@ -153,6 +157,8 @@ abstract contract Staking1155 is ReentrancyGuard, IStaking1155 {
         }
 
         StakingCondition memory _defaultCondition = defaultCondition[nextDefaultConditionId - 1];
+        require(_defaultTimeUnit != _defaultCondition.timeUnit, "Default time-unit unchanged.");
+
         _setDefaultStakingCondition(_defaultTimeUnit, _defaultCondition.rewardsPerUnitTime);
 
         emit UpdatedDefaultTimeUnit(_defaultCondition.timeUnit, _defaultTimeUnit);
@@ -172,6 +178,8 @@ abstract contract Staking1155 is ReentrancyGuard, IStaking1155 {
         }
 
         StakingCondition memory _defaultCondition = defaultCondition[nextDefaultConditionId - 1];
+        require(_defaultRewardsPerUnitTime != _defaultCondition.rewardsPerUnitTime, "Default reward unchanged.");
+
         _setDefaultStakingCondition(_defaultCondition.timeUnit, _defaultRewardsPerUnitTime);
 
         emit UpdatedDefaultRewardsPerUnitTime(_defaultCondition.rewardsPerUnitTime, _defaultRewardsPerUnitTime);
diff --git a/contracts/extension/Staking1155Upgradeable.sol b/contracts/extension/Staking1155Upgradeable.sol
index a0fc25a38..f546ee549 100644
--- a/contracts/extension/Staking1155Upgradeable.sol
+++ b/contracts/extension/Staking1155Upgradeable.sol
@@ -112,6 +112,8 @@ abstract contract Staking1155Upgradeable is ReentrancyGuardUpgradeable, IStaking
         StakingCondition memory condition = _nextConditionId == 0
             ? defaultCondition[nextDefaultConditionId - 1]
             : stakingConditions[_tokenId][_nextConditionId - 1];
+        require(_timeUnit != condition.timeUnit, "Time-unit unchanged.");
+
         _setStakingCondition(_tokenId, _timeUnit, condition.rewardsPerUnitTime);
 
         emit UpdatedTimeUnit(_tokenId, condition.timeUnit, _timeUnit);
@@ -136,6 +138,8 @@ abstract contract Staking1155Upgradeable is ReentrancyGuardUpgradeable, IStaking
         StakingCondition memory condition = _nextConditionId == 0
             ? defaultCondition[nextDefaultConditionId - 1]
             : stakingConditions[_tokenId][_nextConditionId - 1];
+        require(_rewardsPerUnitTime != condition.rewardsPerUnitTime, "Reward unchanged.");
+
         _setStakingCondition(_tokenId, condition.timeUnit, _rewardsPerUnitTime);
 
         emit UpdatedRewardsPerUnitTime(_tokenId, condition.rewardsPerUnitTime, _rewardsPerUnitTime);
@@ -155,6 +159,8 @@ abstract contract Staking1155Upgradeable is ReentrancyGuardUpgradeable, IStaking
         }
 
         StakingCondition memory _defaultCondition = defaultCondition[nextDefaultConditionId - 1];
+        require(_defaultTimeUnit != _defaultCondition.timeUnit, "Default time-unit unchanged.");
+
         _setDefaultStakingCondition(_defaultTimeUnit, _defaultCondition.rewardsPerUnitTime);
 
         emit UpdatedDefaultTimeUnit(_defaultCondition.timeUnit, _defaultTimeUnit);
@@ -174,6 +180,8 @@ abstract contract Staking1155Upgradeable is ReentrancyGuardUpgradeable, IStaking
         }
 
         StakingCondition memory _defaultCondition = defaultCondition[nextDefaultConditionId - 1];
+        require(_defaultRewardsPerUnitTime != _defaultCondition.rewardsPerUnitTime, "Default reward unchanged.");
+
         _setDefaultStakingCondition(_defaultCondition.timeUnit, _defaultRewardsPerUnitTime);
 
         emit UpdatedDefaultRewardsPerUnitTime(_defaultCondition.rewardsPerUnitTime, _defaultRewardsPerUnitTime);
diff --git a/contracts/extension/Staking20.sol b/contracts/extension/Staking20.sol
index abbf51b6d..4b38e49a1 100644
--- a/contracts/extension/Staking20.sol
+++ b/contracts/extension/Staking20.sol
@@ -101,6 +101,8 @@ abstract contract Staking20 is ReentrancyGuard, IStaking20 {
         }
 
         StakingCondition memory condition = stakingConditions[nextConditionId - 1];
+        require(_timeUnit != condition.timeUnit, "Time-unit unchanged.");
+
         _setStakingCondition(_timeUnit, condition.rewardRatioNumerator, condition.rewardRatioDenominator);
 
         emit UpdatedTimeUnit(condition.timeUnit, _timeUnit);
@@ -123,6 +125,10 @@ abstract contract Staking20 is ReentrancyGuard, IStaking20 {
         }
 
         StakingCondition memory condition = stakingConditions[nextConditionId - 1];
+        require(
+            _numerator != condition.rewardRatioNumerator || _denominator != condition.rewardRatioDenominator,
+            "Reward ratio unchanged."
+        );
         _setStakingCondition(condition.timeUnit, _numerator, _denominator);
 
         emit UpdatedRewardRatio(
diff --git a/contracts/extension/Staking20Upgradeable.sol b/contracts/extension/Staking20Upgradeable.sol
index d88d574dd..b1b8bbb09 100644
--- a/contracts/extension/Staking20Upgradeable.sol
+++ b/contracts/extension/Staking20Upgradeable.sol
@@ -103,6 +103,8 @@ abstract contract Staking20Upgradeable is ReentrancyGuardUpgradeable, IStaking20
         }
 
         StakingCondition memory condition = stakingConditions[nextConditionId - 1];
+        require(_timeUnit != condition.timeUnit, "Time-unit unchanged.");
+
         _setStakingCondition(_timeUnit, condition.rewardRatioNumerator, condition.rewardRatioDenominator);
 
         emit UpdatedTimeUnit(condition.timeUnit, _timeUnit);
@@ -125,6 +127,10 @@ abstract contract Staking20Upgradeable is ReentrancyGuardUpgradeable, IStaking20
         }
 
         StakingCondition memory condition = stakingConditions[nextConditionId - 1];
+        require(
+            _numerator != condition.rewardRatioNumerator || _denominator != condition.rewardRatioDenominator,
+            "Reward ratio unchanged."
+        );
         _setStakingCondition(condition.timeUnit, _numerator, _denominator);
 
         emit UpdatedRewardRatio(
diff --git a/contracts/extension/Staking721.sol b/contracts/extension/Staking721.sol
index 729c711e3..e7a8bcc3f 100644
--- a/contracts/extension/Staking721.sol
+++ b/contracts/extension/Staking721.sol
@@ -99,6 +99,8 @@ abstract contract Staking721 is ReentrancyGuard, IStaking721 {
         }
 
         StakingCondition memory condition = stakingConditions[nextConditionId - 1];
+        require(_timeUnit != condition.timeUnit, "Time-unit unchanged.");
+
         _setStakingCondition(_timeUnit, condition.rewardsPerUnitTime);
 
         emit UpdatedTimeUnit(condition.timeUnit, _timeUnit);
@@ -119,6 +121,8 @@ abstract contract Staking721 is ReentrancyGuard, IStaking721 {
         }
 
         StakingCondition memory condition = stakingConditions[nextConditionId - 1];
+        require(_rewardsPerUnitTime != condition.rewardsPerUnitTime, "Reward unchanged.");
+
         _setStakingCondition(condition.timeUnit, _rewardsPerUnitTime);
 
         emit UpdatedRewardsPerUnitTime(condition.rewardsPerUnitTime, _rewardsPerUnitTime);
diff --git a/contracts/extension/Staking721Upgradeable.sol b/contracts/extension/Staking721Upgradeable.sol
index 41304c452..0cc7899ea 100644
--- a/contracts/extension/Staking721Upgradeable.sol
+++ b/contracts/extension/Staking721Upgradeable.sol
@@ -101,6 +101,8 @@ abstract contract Staking721Upgradeable is ReentrancyGuardUpgradeable, IStaking7
         }
 
         StakingCondition memory condition = stakingConditions[nextConditionId - 1];
+        require(_timeUnit != condition.timeUnit, "Time-unit unchanged.");
+
         _setStakingCondition(_timeUnit, condition.rewardsPerUnitTime);
 
         emit UpdatedTimeUnit(condition.timeUnit, _timeUnit);
@@ -121,6 +123,8 @@ abstract contract Staking721Upgradeable is ReentrancyGuardUpgradeable, IStaking7
         }
 
         StakingCondition memory condition = stakingConditions[nextConditionId - 1];
+        require(_rewardsPerUnitTime != condition.rewardsPerUnitTime, "Reward unchanged.");
+
         _setStakingCondition(condition.timeUnit, _rewardsPerUnitTime);
 
         emit UpdatedRewardsPerUnitTime(condition.rewardsPerUnitTime, _rewardsPerUnitTime);
diff --git a/src/test/staking/EditionStake.t.sol b/src/test/staking/EditionStake.t.sol
index 91a332d65..3c8a36512 100644
--- a/src/test/staking/EditionStake.t.sol
+++ b/src/test/staking/EditionStake.t.sol
@@ -1079,7 +1079,7 @@ contract Macro_EditionStakeTest is BaseTest {
         stakeContract.withdraw(2, tokenAmount);
 
         // timeUnit can't be changed back to a nonzero value
-        newTimeUnit = 60;
+        newTimeUnit = 40;
         // vm.expectRevert(stdError.divisionError);
         vm.prank(deployer);
         stakeContract.setDefaultTimeUnit(newTimeUnit);
diff --git a/src/test/staking/NFTStake.t.sol b/src/test/staking/NFTStake.t.sol
index 802896194..15c808e01 100644
--- a/src/test/staking/NFTStake.t.sol
+++ b/src/test/staking/NFTStake.t.sol
@@ -287,7 +287,7 @@ contract NFTStakeTest is BaseTest {
         assertEq(timeUnit, stakeContract.getTimeUnit());
 
         // set new value and check
-        uint256 newTimeUnit = 1 minutes;
+        uint256 newTimeUnit = 2 minutes;
         vm.prank(deployer);
         stakeContract.setTimeUnit(newTimeUnit);
         assertEq(newTimeUnit, stakeContract.getTimeUnit());