I am experiencing exactly the same issue.
@jas.singh99 Have you tried to create a session from the Hololens and join the session from the PC? I have done it and it works, but I would need the other way round!
Obviously firewall rules have been created to avoid blocks and I have the same problem even if I use the approach of the HL2Collab example to join a session ( MixedReality-Unreal-Samples/HL2Collab at master · microsoft/MixedReality-Unreal-Samples · GitHub )
Any ideas?