Merchant APP ID (Alphanumeric - Length of 32 chars and special chars $@%#)
Merchant APP KEY (Alphanumeric - Length of 32 chars and special chars $@%#)
EPI is an end point identifier, Identify the device on valor infrastructure, it's a 10 digit number starts with 2
Cancel E-Page Sale
Epage UID to update and resend
200