git push permission error message contains "read", but should be "write" permission error

I had created a project in Stash with an empty git repository.
Then I had added my public key to the project with "READ" permission (not "read/write".

Then I could clone the project in my local development environment, but I could not push my changes to the empty project, because git gives me this error:

fatal: remote error: Insufficient permissions
You do not have permission to push to the repository mytestprojectrepo in
project MyTestProject
fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists.

This error strongly suggests that the "read" permissions are not properly set in Stash, but they are!

When I re-add the public key to my Stash project, but now with "read/write" permissions, the "problem" is gone.

Just a triviality, but still ...