User using router ip address!!!

Hi, I have sometimes problem when lame wireless user set his IP same as the router. There is static arp on the router and he have no Internet, but everyone else too.

I have wds and all interfaces in bridge 1.

Where and how can I set static arp in Mikrotik to lock any communication for wireless user using wrong IP address? Which interface to use? I don’t want him to make problems for other wireless users on the same interface.

use hotspot with universal client and it will not matter what user sets on his computer …