Is this a custom field? As JIRA doesn't provide a system field "created by" system field. If its a custom field then you can remove the field from the "edit" screen in order to make sure it's only filled at the time of creation.
If you are talking about "reporter" field then you can follow the approach as suggested by @Udo Brand
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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