Lost user access to a repository

Everything worked fine until I added another user to a remote repository. The user didn’t work even though it should, so I deleted it. Now, I cannot connect to the repository even with the original user even though nothing else changed (and I can see the original user is still in the repository). All I get when connecting from a client machine is:

Connect Error: INTERNAL: internal server error: connect error: error opening repository: error connecting to API server: unable to establish session for purpose=: error establishing session: unable to initialize session: rpc error: code = PermissionDenied desc = access denied for admin@macbook: EOF

The problem was that I put wrong passwords in KOPIA_PASSWORD variable. Sometimes it needs to be user password (when backing up), sometimes repo password (when starting kopia server). Confusing.