Yes it could, so check the users setup in both servers. As a general rule first check with the same user login directly on the slave, if you can login directly you have a chance that you can also login through the master.
As this is not related to software development with the MIP SDK, which is the focus of this forum, please ask in the support community if needing further troubleshooting tips, you should get better help from the partners using the support community.