A common problem with a GPRS credit card terminal is the connection with a venue or location. Please use the following steps to ensure the card terminal is displaying the correct information on screen before attempting to use the device.

  • Please ensure the card machine displays GPRS on the screen.
  • Ensure network bars are displayed on the screen and check the amount of bars available (5 being extremely good).
  • Most importantly, ensure the card terminal displays a network (Orange, EE, T-Mobile, O2, Vodafone or Datasim). If the network is not displayed the card machine will NOT connect.#


When a card machine is trying to process a transaction and the payment is being declined, the unit displays ‘INVALID MERCHANT’ and the Chip and PIN terminal is not connected to your merchant account correctly. All units are deployed by WTS fully configured, meaning the Invalid Merchant error code is generally caused from an error at the bank’s end. The problem predominately occurs if the merchant account has been closed or if the Chip and PIN terminal has been removed from the banking system. To solve this issue please call the designated support lines provided supplied in the WTS help book.