missing or invalid provider NPI

Amerigroup uses provider information from TMHP. Make sure your provider is enrolled with TMHP.
according to Amerigroup EDI you can call 800-925-9126

If you have other providers in your practice, make sure Amerigroup has their NPI on file.
If you have an NPI for your practice, make sure Amerigroup has that NPI on file.

Verify the NPI, Taxonomy Code and address that they have on file.
 
It also may be caused by a the Facility NPI (Case/Account/Facility)
 
and/or the Referring Provider NPI (Case/Account/Referring Provider)