The most common reason for the "Medicaid number missing" occurs when the client is included in a Cost Center that is excluded from DODD is because the service that is being billed is not included in the Cost Center.
For example, suppose the "Medicaid number missing" error is occuring for Non-Medical Transportation. Let's take a look at the Cost Center setup for the 'County Board' Cost Center:
It looks like the Transportation is included in the Cost Center. But looking more closely, 'Transportation (Miles)' is missing. And in fact, the error is occuring on Transportation being billed as "Per Mile".
This same scenario can occur for other services. Maybe you are billing for Group Employment and getting this error. Be sure all services that might be used in a Cost Center are "checked".