@SarnaGuptaS

Such type of issues occur due to cluster instability. Admin studio relies on hazelcast in-memory cache to fetch listener's information. 

If any node leaves cluster or improper shutdown of node then entire cluster gets disturbed which results in such issues.

---> A clean cluster restart is required to resolve such issues.

This issue is typically due to the hazelcast cache becoming out of synch, which is in turn often caused by not starting your stream nodes first. Pega recommends ensuring that your stream nodes stand alone.

https://community.pega.com/knowledgebase/articles/decision-management/84/operating-stream-service

In later releases of Pega we are currently developing code which exposes dropped nodes, lost partitions, and failed merges, among other events of interest. 

As noted in documentation,  Pega recommends not mixing stream services with any other functions:  https://community.pega.com/knowledgebase/articles/decision-management/84/configuring-stream-service

A server start alone should succeed in clearing the hazelcast cache.

---> Can you confirm whether this has been done?  

@SarnaGuptaS  Still have the issue? pls try with the clean re-start( Clear the App and DB cache).

@MarijeSchillern  @Deven  No Luck after following the below suggested ways, Could anyone please help me with the other possible ways to fix this.

Thanks in advance,

Sarna

@SarnaGuptaS Its looks like Pega platform configuration issue if its Pega cloud ,better reach out to them, if on premise you need to engage admin support team.

@SarnaGuptaS

Are you getting any exceptions getting captured in PDC related to hazlecast...