Problem with access two SXT Mikrotiks in bridge mode in the same network

Hello, I have two Mikrotiks in my network RB951Ui-2nD as a main router connected to my ISP and SXT (Lite 2) as a bridge client to another AP and everything works ok, now I bought additional SXT2 RBSXTG2HnD which I want to run as a bridge AP to my network. Problem is when I connect the new SXT2 RBSXTG2HnD to my network switch and start configuration everything is fine until I activate bridge mode in this SXT2 RBSXTG2HnD then this new Mikrotik disappears from my network and I cannot access it. I have to connect it directly to my notebook LAN card where I can normally connect and administrate it. I did many configuration trials but everytime when the bridge interface is activated the new Mikrotik disappears from network. During the tests I recognized that the problem is only when all Mikrotiks are connected to the same network when I disconnect the other Mikrotiks from my network the new one appears and administration is normally possible. All Mikrotiks have different IP address from the 192.168.2.0 range so there is no IP collision. I don´t understand that, I use many network devices and never had such problem. There is some relation to bridge mode but… ???

Did you perhaps import backup from SXT to the other to speed up your deployment [I know that’s exactly what I would have done]? Backup contains MAC addresses so doing this will cause, ahem, interesting behaviour.