Asus Aimesh error?

I have a DSL-AC68U as the main router in an aimesh configuration. Then i have an RT-AC68U as an AIMESH node. The issue im having is im getting both signals of the router in my bedroom and it always switches between them, so im trying to lower the TX power and the roaming assist, but when i do change them it comes up with this message.

Any reason why? The only thing i can think of is because one is a DSL version? I moved the node as far away as possible, it is wired via gigabit ethernet.