GET|MY|YOUR DOCTOR CLIENT ID: WHERE'S MINE?

So, I just require to pay the doctor's bill. Easy, right? Not so fast! The website says I need enter paymydoctor where is client id my Client ID, but where is mine? This whole thing is getting me crazy! I've checked everywhere, but it darn Client ID looks to be lost. Maybe I just missed something? Could you reach out to customer assistance?