ALTECH UEC OVHD DECODER 4139 DISPLAYS E06 ERROR

My new Altech UEC OVHD DSD 4139 only worked for a day after installation. The following day it could not work, kept displaying an Error message, E06: \THIS STB OR SMART CARD IS NOT ACTIVATED . PLEASE ACTIVATED USING THE OVHD USSD OR REFER TO THE CUSTOMER CARE NO IN THE USER MANUAL". I ACTIVATED a couple of times using the OVHD USSD but that did not clear the message. The Customer Care No on the Brochure and packaging rang unanswered. I am frustrated as I cannot watch TV and I don't know what else I should do to get this sorted.. """