Please notify us if you think your bill is inaccurate. Written disputes should be mailed to Patient Financial Services at P.O. Box 20894, Fountain Valley, CA 92728-0894. You can also fax to (714) 377-3572. If you are writing to us, please include: Your name and account number. The charge(s) that you feel may be inaccurate. An explanation of why you believe the bill is in error. If you wish to discuss your concerns with a representative, we invite you to call Patient Financial Services.