HELP running diagnostics for Applecare

[Heartex]

Ok, so finally got my 2019 MBP 16in from China. Beautiful machine. Got my laptop through Expercom but they ordered it straight from China. Got a great deal also on AppleCare there so bought it too. $329
So needed to call and run Diagnostics to get AppleCare. This is where my problem starts. Stayed on phone over 30 minutes trying to get diagnostic to work. They said Press power button and OP and D. It go to black screen & internet connection and when I get that hooked up...NOTHING. It does not go to diagnostic. Over and over with hard rest, Pram and Scm. Called Apple support they said just press power button and only press D. Pulls up diagnostic and they got report. They wanted to sell AppleCare but wouldn’t match Expercom. Called Expercom back I went through Apple method and they can’t get report.Tried Expercom... nothing.
They have done several and not had this problem, call tomorrow. I said Hey I just spent thousand and thousands on this machine and it they can’t get it to work I want my money back. Who had gone through diagnostics and how? If Expercom says the book says to do it and other machines have done it do I say I want my money back? I don’t want to start with any issue. Help!

 

[Sanpete]

It's a standard test, should work. Call again tomorrow, and if they can't get it ironed out, you could return it as defective for a full refund. Odd that the regular method works, including sending the report, which goes over the internet, but the internet method doesn't work. If you have a firewall, maybe there's an issue there.

 

[Heartex]

FYI: It was my wifi. Took my laptop to my office and it went straight to Diagnostic internet. Not sure what is up with my internet. It is not fancy or encrypted just straight forward router. But problem solved.