Hello, pelase can anybody help me?

Ideally with ssh knowledge.. Official support comes to me that he does not know what I'm talking about..

1. I have a public IP address assigned to my miners (they are in external "warehouse" of IT company), so that I can remotely manage them but after a while the logon stops functioning.. Maybe few days working well.. Even did not help HW reset, shutdown, power on, etc.. The login page is loaded but after clicking on login nothing is happening but miners obviously minning when I check them on the pool page, BUT - point 2

2. when mining on nicehash my miners always at 20:00 - 23:30 all fall, then try to start.. what it is ? of course I can not change the pool when I can not log in, cant update firmware (i have A9 b29+_20180911_095547, new is A9 b29+_20181009_094439) .. z9 mini works without any problems how to login (also remotely) also mining..

Can anybody help me with ssh? I need restart them, update firmware and understand what's going on :-(...