You can find an answer to your question in the following article:
The idea is:
To Set epic link you have to use the same api as to set any other custom field value to an issue. First you get reference to the Epic link field. Secondly you set it using MutableIssue or IssueService like in the example above.
Hey Community mates! Claire here from the Software Product Marketing team. We all know software development changes rapidly, and it's often tough to keep up. But from our research, we've found the h...
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