Cannot create subdomains

When I create subdomains for any domains in server they all do not exist. They make folder in account folder but thats it no access to them via subdomain.domain.net

I guess you are talking about DNS. Make sure you do not forget about A record for the subdomain

This was caused by a misconfigured dns records for all account domains. i fixed this by setting proper dns nameservers for server and in turn changes dns zones for all domains under all accounts.

On creation of subdomains through admin/index.php?module=add_subdomain or user account alternative I created them without having to tweak the A records in DNS Functions.