Issue Error while deleting database user via plesk.

[Aelna]

I have been trying to delete a database user or assign the same db user to a database from my plesk panel but it is throwing below error:

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Delete database user failed: mssqlmng failed: Cannot drop schema 'user' because it is being referenced by object 'ACGroup'.
at (VADOConnection::execute line 78)
at execute console command --del-user(vconsoleapp::start line 93)
at execute "C:\Program Files (x86)\Plesk\admin\bin\mssqlmng" --del-user "--server=54.36.230.134,1433" "--login=sa" "--password=*" "--database=db" "--user-login=user"(vconsoleapp::run line 110)
(Error code 1)
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