database service not imported but it says already imported

in many cases, i face this issue
Database service does not exist in the list. when i try to import them, it says already imported?

and it does not allow me to add them. the picture clarify the issue.

I solved this once by renaming the collection name. however, it is not a good way. what cause the problem and what is the best way to solve?
2 people have
this problem