When priority is raised on an issue, git2gus creates a new issue instead of updating the existing

As a repository maintainer, I have an existing Github issue labelled "BUG P3" and linked to an ADM_Work record. I'd like to raise the priority to "BUG P2" and have the ADM_Work update.

However, if I remove the P3 label and add P2 at the same time, a duplicate issue is opened in the linked repository. That happened on this same issue actually. Screenshot attached.