Using last version - Cannot make 2 urbackup clients went online again

I’m using last version - Cannot make 2 urbackup clients went online again

urbackup:
Server - UrBackup 2.5.33
Client - Urbackup 2.5.25

Problem:
Two urbackup clients were making images perfectly, but start displaying as Offline in the Urbackup Web Console

One client machine is a Windows 7 machine (urbackup client was working)

And the another client machine is a Windows Server 2016

I can’t make them go Online again in Urbackup

I read a lot on the web about this problem, tried a lot of things (open TCP and UDP ports in urbackup server and client , etc),
but it doesn’t work