Thanks for your private message.
I checked that partner user is not associated with partner company (1st step mentioned below). Please follow below and let me know if you have any question.
SNTC Portal Administration and Management Guide: https://www.cisco.com/c/en/us/support/docs/services/sntc/portal_administration.html
CBR admin/user steps:
Step 1 (This step is done by Partner company DA): Look for topic 'Add New Users to the Portal and Assign Roles' on above link. (NOTE: this step has to be done before step 2)
Step 2 (Only done by Customer company DA to assign CBR admin/user role): Look for topic 'Add Partners to the Portal and Assign Roles' on above link.
Request to become Partner DA for partner company:
Look for topic: 'Request Partner Delegated Administrator (For Partners Only)'