Unable to assign a case to someone

Summary:

I'm unable to assign a case to a resource member.

The error message just says " Please try again later and if the issue persists, contact your help desk."

What roles/privileges/duties do I need to have as an administrator? (Also our custom case manager role does not have the ability to assign a case either.)

Or is it a scheduled job that I need to run? Thank you.

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Version (include the version you are using, if applicable):

24D

Code Snippet (add any code snippets that support your topic, if applicable):