Domain displays the content from the old server despite the fact that DNS were propagated globally already and now domain is pointing to the new server IP.
If new IP and domain name are added to the 'hosts' file in
C:\Windows\System32\drivers\etc, domain loads correct content from the new server:
DNS has different settings on a local computer (or local network) where from domain is opened: local computer is setup with different DNS resolution settings, so when domain is opened in a browser, it tries to connect to a different IP (old server IP)
Contact your network provider for assistance