This means the merchant is attempting to run a transaction that is not allowed by the Host (Processor).
If you believe this to be an error check the parameters on your file to ensure it is set up correctly and contact the Host to validate everything in their system is set up correctly.
Example:
- The host is First Data Omaha
- You attempt to process a Debit Transaction
- Error: Invalid Transaction Type
Reason: First Data EMV Transactions must be initiated as a Credit Sale. If the chip determines it is a Debit Card it will ask for a Debit PIN.