MAKING A PAYMENT MY DOCTOR: WHERE'S MY CLIENT ID?

So, I'm trying to pay my doctor's fees, and it says I need a client ID. Problem is: I can't find it anywhere! I've looked in my emails. Did my doctor's office send it to me? Do they have a separate portal? Any tips for finding this client ID would be really helpful. Getting into Veradigm Pay My Doctor and Payment Issues Are you facing problems