Ar750s 5g is turning off

Hi, I just received my router and used few hours with iOS 12 and lineage. I had to reset many times in half a day as I faced some issues. Main one was 5g that turned off, disappeared and cannot be reactivated without resetting. Minor, when connecting with a wireless network it returned “timeout” but then it was connected. Maybe I am doing something wrong, any help?

I have replied you in support email.