Hotspot disconnects. With weird logs

Hi All. This is my first post here.
I have RB951Ui. Installed as wifi hotspot. Users connect to wifi, logged in there, serfing internet, all good. Then something going wrong and users have disconnect and this disconnections is repeating about every 10 mins, also i got weird log :

I’m not setup any accounting. In hotspot profile:

Also i dont have any RADIUS servers.

What i need to avoid this messages in logs. And i need that hotspot users be connected without any disconnections. Can anybody help me with this?