Creating a merge request from a fork of the repository navigates to source repository and gives 404

How can I reproduce the bug?

1. Create a fork of the repository
2. Make some changes and create a merge request for the main repository
3. Don't merge changes
4. Make some other changes on fork repository
5. Try to create 1 more request
6. Receive an error message that there is already an open request
7. Follow the link where this open request should be, but it is not there, a non-existent request on the fork opens