new exchange 2019 servers in 2013 exchange env are added to upgarde, at some point i configured the internal urls and that seems to crash exch PS

not able to connect to any exchange server when i open exch powershell from newly installed 2019 server

i followed the steps from the exchange deployment assistant, when i reached to the configure urls part the below was one of the commands i ran which i believe might have caused the issue as it was working fine prior 

i set the hostname 1st to the server fqdn

Set-PowerShellVirtualDirectory "$HostName\PowerShell (Default Web Site)" -InternalUrl ((Get-PowerShellVirtualDirectory "$HostName\PowerShell (Default Web Site)").ExternalUrl)

i can share the error i am getting is  domain\servername$ could not be found

the domain in the error is not FQDN, like maher only not maher.com

anyway to fix that pls, need to use the exch PS on these new server to complete the migration for the upgrade from 2013