There's been a lot of trouble with NAB EPX/Velocity Builds recently. To remedy that here is documentation that has worked on at least two different NAB merchants.
Application Name: EPX Processor-HC-Retail-S300
Version: V1.00.03E
In particular this is good for merchants who want to disable signature on the pin pad, but want NFC (google pay etc) enabled.
Other settings such as communication protocols need to be updated aswell (depending on Windows or Android), or whatever settings are requested.
If a update/download does not work, you might need to do a firmware reset and redownload.
The Var Sheets coming from NAB usually include a 5 part code.
Cust_nbr: usually 3001
Customer_nbr: the merchant number
DBA_nbr: usually 1
Term_nbr: terminal number make sure this is correct.