If you own the filter or the filter is shared with you the filter should show up in the list, but if the filter is not showing up in the list for the issue sources when creating or editing the plan the only thing I could think of, would be if you do not have permissions on the filter.
I would say check the filter owner, and make sure you have permissions to the filter, you can change ownership of the filter if you have Administer Jira global permission and grant the appropriate permissions as the filter owner.
Let me know if this is the case.
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