UPSET PAY MY DOCTOR: WHERE'S MY CLIENT ID?

Okay, so, I need to pay my doctor's invoice. I logged in the portal and it says I need a client ID. But, I can't that! What am I supposed to do? Is there a way to find my client ID? Please figure this out. It's really annoying having to stop payment because of this. Using Veradigm & Pay My Doctor Navigating healthcare expenses can be a difficult