NEED TO SETTLE MY DOCTOR: WHERE'S MY CLIENT ID?

So, I'm trying to pay my medical bill, and it says I need a client ID. Problem is: I can't find it anywhere! Checked the paperwork. Did my doctor's office send it to me? Do they have a online system? Any suggestions about getting this client ID would be super useful. Logging in to Veradigm Pay My Doctor with Payment Complications Are you facin