Blue Cross Blue Shield has an alpha-prefix at the front of all members primary ID (subscriber ID). This alpha-prefix is very important for Blue Cross Blue Shield. They use the alpha-prefix to route claims to the appropriate state (an alpha-prefix represents a state).
The payer is rejecting stating the the alpha-prefix you have entered is not valid.
You will want to edit the insurance card (the primary ID) and make sure the primary ID matches what is on the insurance card. Once you have made your updates, you can then resubmit this claim.