Hello,

I'm facing issue that few Wireless devices which i have on floor 1 - Master DHCP Router Wifi (AP-A) are time to time connect to the Slave AP on Floor 0 - router Wifi (AP-B) and it leads to weak / poor signal or complete disconnect from Wireless network. Even i need to restart those clients to connect again.

So instead of putting all clients MACs on AP-B as White List - "Wireless Tables - Access list"
Can i set "Black List" for few clients?

So i can be sure that those few clients stay only on AP-A.

Thanks

Depends on which wireless package respectively menu you are using. If it's the Wireless menu, it can be done through the connect list:
If the WiFi interfaces are in the Wifiwave2 or WiFi menu, then the blocking rule would be set up in the access list:

Thanks for suggestion.
Main Router 1st AP - hAP AX3
The 2nd AP is - CRS125-24G-1S-2HnD (so i assume no Wifiwave2 support)

To be honest i haven't really looked yet into the new changes Wireless / Wifiwave2 changes (i believe since 7.10+)
Here i'm adding new / 2nd Wifi interface let's say wlan2 and i will list MACs which won't be able to connect?

Or i will use it on "wlan1" with an extra rule?

Seems like this did the trick
What I've realized now i could also add some "Signal Strength Range" limit (i believe i read about it somewhere)
So if it's weaker then XX devices wouldn't connect, so perhaps this way i don't need to set it for each MAC...right?

Yes, it could be done also like that but you'll have to setup the limit most probably based on trial and error