I would start by looking through the JIRA log files to see if any error gets thrown during this operation. When I have encountered this in the past, it usually had something to do with data inconsistency and the index becoming impacted as a result.
See here for some potentially related documentation:
I’m a designer on the Jira team. For a long time, I’ve fielded questions from other designers about how they should be using Jira Software with their design team. I’ve also heard feedback from other ...
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