How do you activate a PIM role that you have been assigned in a B2B relationship, where the role is not in your default tenant? When you go to MyRoles it only shows the roles for your default tenant, and I do not see any way to switch tenants from there.
MyRoles only shows the roles from your default domain.
You have to switch to the guest tenant (top right corner the settings icon left of your user). After that, you can go again to your PIM blade and claim the required role.
I hope this helps!
Best regards, Sebastian