Hi,
Kindly note that forum of windows server branch office mainly supports questions related to branch cache of windows server, which is used to cache content at branch office locations, allowing client computers to access data using LAN rather than slow WAN connections.
But per your description, the problem is more related to another product which we have limited knowledge. Per searching, following links might be helpful:
Remove or replace a resource assignment
https://support.microsoft.com/en-us/office/remove-or-replace-a-resource-assignment-868b650a-4b86-43d8-85a0-c39d382f4db2
Delete resources and users in Project Server
https://learn.microsoft.com/en-us/project/delete-resources-and-users-in-project-server
If they didn't work, you could post new question in the Answers forum for more assistance of the experts there.
Microsoft 365 and Office
https://answers.microsoft.com/en-us/msoffice/forum/msoffice_project?sort=LastReplyDate&dir=Desc&tab=All&status=all&mod=&modAge=&advFil=&postedAfter=&postedBefore=&threadType=all&isFilterExpanded=false&page=1
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Hope this helps and please help to accept as Answer if the response is useful.
Thanks,
Jenny