diff --git a/.changeset/funny-cherries-drive.md b/.changeset/funny-cherries-drive.md
new file mode 100644
index 0000000000..922a306896
--- /dev/null
+++ b/.changeset/funny-cherries-drive.md
@@ -0,0 +1,5 @@
+---
+"@kadena/graph": patch
+---
+
+Fixed transaction subscription issue with mempool and completed transactions
diff --git a/packages/apps/graph/src/graph/mappers/transaction-mapper.ts b/packages/apps/graph/src/graph/mappers/transaction-mapper.ts
index 9babdb80c6..78452b3f9a 100644
--- a/packages/apps/graph/src/graph/mappers/transaction-mapper.ts
+++ b/packages/apps/graph/src/graph/mappers/transaction-mapper.ts
@@ -28,7 +28,7 @@ export function mempoolTransactionMapper(mempoolData: any): Transaction {
   // Convert creationTime to milliseconds (mempool has it in epoch format in seconds)
   mempoolTx.cmd.meta.creationTime = mempoolTx.cmd.meta.creationTime * 1000;
 
-  const transaction = {
+  const transaction: Transaction = {
     requestKey: mempoolTx.hash,
     badResult: null,
     continuation: null,
@@ -51,7 +51,9 @@ export function mempoolTransactionMapper(mempoolData: any): Transaction {
     rollback: mempoolTx.cmd.payload.rollback,
     proof: mempoolTx.cmd.payload.proof,
     senderAccount: mempoolTx.cmd.meta.sender,
-    step: BigInt(mempoolTx.cmd.payload.step),
+    step: mempoolTx.cmd.payload.step
+      ? BigInt(mempoolTx.cmd.payload.step)
+      : mempoolTx.cmd.payload.step,
     ttl: BigInt(mempoolTx.cmd.meta.ttl),
   };
 
diff --git a/packages/apps/graph/src/graph/objects/transaction.ts b/packages/apps/graph/src/graph/objects/transaction.ts
index 67fee6f83e..de006405d1 100644
--- a/packages/apps/graph/src/graph/objects/transaction.ts
+++ b/packages/apps/graph/src/graph/objects/transaction.ts
@@ -1,3 +1,4 @@
+import type { Signer } from '@prisma/client';
 import { Prisma } from '@prisma/client';
 import { getMempoolTransactionStatus } from '@services/chainweb-node/mempool';
 import { normalizeError } from '@utils/errors';
@@ -22,27 +23,33 @@ export default builder.prismaNode(Prisma.ModelName.Transaction, {
     sigs: t.field({
       type: [TransactionSigs],
       async resolve(parent) {
-        const signers = await signersLoader.load({
-          blockHash: parent.blockHash,
-          requestKey: parent.requestKey,
-          chainId: parent.chainId.toString(),
-        });
+        if (!nullishOrEmpty(parent.blockHash)) {
+          const signers = await signersLoader.load({
+            blockHash: parent.blockHash,
+            requestKey: parent.requestKey,
+            chainId: parent.chainId.toString(),
+          });
 
-        return signers.map((signer) => ({
-          sig: signer.signature,
-        }));
+          return signers.map((signer) => ({
+            sig: signer.signature,
+          }));
+        }
+        return [];
       },
     }),
     cmd: t.field({
       type: TransactionCommand,
 
-      async resolve(parent, __args, context) {
+      async resolve(parent, __args) {
         try {
-          const signers = await signersLoader.load({
-            blockHash: parent.blockHash,
-            requestKey: parent.requestKey,
-            chainId: parent.chainId.toString(),
-          });
+          let signers: Signer[] = [];
+          if (!nullishOrEmpty(parent.blockHash)) {
+            signers = await signersLoader.load({
+              blockHash: parent.blockHash,
+              requestKey: parent.requestKey,
+              chainId: parent.chainId.toString(),
+            });
+          }
 
           return {
             nonce: parent.nonce,
@@ -74,15 +81,18 @@ export default builder.prismaNode(Prisma.ModelName.Transaction, {
       type: TransactonInfo,
       resolve: async (parent) => {
         try {
-          const status = await getMempoolTransactionStatus(
-            parent.requestKey,
-            parent.chainId.toString(),
-          );
+          //This check is important because a transaction can be completed, yet we can still be able to fetch a status from the mempool
+          if (nullishOrEmpty(parent.blockHash)) {
+            const status = await getMempoolTransactionStatus(
+              parent.requestKey,
+              parent.chainId.toString(),
+            );
 
-          if (!nullishOrEmpty(status) && status) {
-            return {
-              status,
-            };
+            if (!nullishOrEmpty(status) && status) {
+              return {
+                status,
+              };
+            }
           }
 
           return {
diff --git a/packages/apps/graph/src/graph/subscription/transaction.ts b/packages/apps/graph/src/graph/subscription/transaction.ts
index f06b0b5901..ba129935f1 100644
--- a/packages/apps/graph/src/graph/subscription/transaction.ts
+++ b/packages/apps/graph/src/graph/subscription/transaction.ts
@@ -59,6 +59,8 @@ async function* iteratorFn(
 
       if (mempoolResponse) {
         yield mempoolResponse;
+      } else {
+        yield undefined;
       }
     }
 
diff --git a/packages/apps/graph/src/services/chainweb-node/mempool.ts b/packages/apps/graph/src/services/chainweb-node/mempool.ts
index 648d344f7d..8c0d907b84 100644
--- a/packages/apps/graph/src/services/chainweb-node/mempool.ts
+++ b/packages/apps/graph/src/services/chainweb-node/mempool.ts
@@ -100,11 +100,19 @@ export async function mempoolLookup(
           });
 
           res.on('end', () => {
-            resolve(JSON.parse(data));
+            try {
+              resolve(JSON.parse(data));
+            } catch (error) {
+              reject(
+                new MempoolError(
+                  'Error occurred while processing response data.',
+                  error,
+                ),
+              );
+            }
           });
         },
       );
-
       req.on('error', (error) => {
         reject(
           new MempoolError(