diff --git a/pulsar-functions/instance/src/main/java/org/apache/pulsar/functions/instance/InstanceUtils.java b/pulsar-functions/instance/src/main/java/org/apache/pulsar/functions/instance/InstanceUtils.java
index 024599c6db134..b0cb5e6c5236a 100644
--- a/pulsar-functions/instance/src/main/java/org/apache/pulsar/functions/instance/InstanceUtils.java
+++ b/pulsar-functions/instance/src/main/java/org/apache/pulsar/functions/instance/InstanceUtils.java
@@ -117,7 +117,9 @@ public Function.FunctionDetails.ComponentType calculateSubjectType(Function.Func
     }
 
     public static String getDefaultSubscriptionName(String tenant, String namespace, String name) {
-        return FunctionCommon.getFullyQualifiedName(tenant, namespace, name);
+        // Hacking this to just return the function name. Using a FQFN breaks the REST endpoints
+        // that deal with subscriptions
+        return name;
     }
 
     public static String getDefaultSubscriptionName(Function.FunctionDetails functionDetails) {
diff --git a/pulsar-functions/instance/src/main/python/python_instance.py b/pulsar-functions/instance/src/main/python/python_instance.py
index fecde7a6e8b1c..1fd67a76b4983 100644
--- a/pulsar-functions/instance/src/main/python/python_instance.py
+++ b/pulsar-functions/instance/src/main/python/python_instance.py
@@ -136,9 +136,8 @@ def run(self):
     if self.instance_config.function_details.source.subscriptionType == Function_pb2.SubscriptionType.Value("FAILOVER"):
       mode = pulsar._pulsar.ConsumerType.Failover
 
-    subscription_name = str(self.instance_config.function_details.tenant) + "/" + \
-                        str(self.instance_config.function_details.namespace) + "/" + \
-                        str(self.instance_config.function_details.name)
+    # Default subscription to function name
+    subscription_name = str(self.instance_config.function_details.name)
 
     properties = util.get_properties(util.getFullyQualifiedFunctionName(
                         self.instance_config.function_details.tenant,