Expect extra time until you get your reimbursement if your claim is erroneously rejected with reason code U6803, indicating ""A GHP MSP Auxiliary record exists, no GHP is indicated on the claim, but dates of service match a GHP occurrence," MAC CGS says on its website. "CGS has a work-around and will continue to work these claims," the MAC says. "However; due to the volume, processing may take additional time. The correction for this issue is scheduled to go into production on June 4, 2018."