We don't recommend having more than one game account per device. However, it is possible if you keep valid restore codes for each of your accounts and follow the sync account flow. Remember that restore codes can only be used 5 times before you will need to generate a new restore code.

Simply follow this flow to transfer between your accounts here.

If you try to add another account and do not have an active restore code for the previous account your progress on the first account may be irretrievably lost.