I am using a RE200 extender connected to my modem/router at 2.4GHz. RE200 is dual band, thus providing both a 2.4GHz and 5GHz extension. I understand that 2.4GHz must be the same channel as my router. This is fine. The problem is that I should be able to change the 5GHz channel, since my router does not use 5GHz, but I am unable to do it.

Any solution?