How to solve persistent "Not connected to repository" issue in Oracle SQL Developer?

Question

Oracle

I am doing an internship in one company and my task for the internship was testing procedures and functions. Having searched the Internet, I found a suitable toolkit in the form of Unit test in Oracle SQL Developer. Having studied the documentation and searched for examples on the Internet, I ran into the problem of creating a repository. Using the examples from the documentation, I created a new user, created a connection under it, and when it came to assigning rights and creating a repository, the process stopped. It seems that new roles are simply not created and this process turns into recursion, which is why the repository is not created. If anyone has come across a similar problem, please help. Thank you in advance.

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