Why do Samsung devices lose connection with WiFi hotspots?

Question

WiFi

Good afternoon.
I installed Unifi AP AC access points - everything seemed to work smoothly, there are no problems with the network on my LG G3, other users (iPhone 5-6, Sony, Chinese) do not complain. But there are a couple of Samsung Galaxy Tab 10.1 tablets, and a Samsung Galaxy phone, probably 5, they constantly lose connection in my WiFi network - they say that the provider's modems are at home - the connection does not break. Connection parameters:
WPA Personal
WPA2 Only
Encription: Auto
Maybe there are some additional ones. settings for samsung? I've never used their devices myself.