DirectAccess error: Windows is unable to resolve DNS names for probes

Hello,

we have a Direct Access Server installed as edge server.

So we have 2 NICs one internal one external. About 2 days ago DirectAccess stopped working.

When I collect logs on a client it shows: "Windows is unable to resolve DNS names for probes"

Interestingly if I use nslookup I am able to resolve internal servernames:

Here also the netsh effectivepolicy:

Could someone lead me in the right direction to solving this issue?

Thanks in advance

Paul