Incorrect billing

I signed up for the double data lte home promotion on 22nd of November, only received the simcard and router about 2 weeks ago. Recently received my bill and it states that there is no double data promotion active and my bill is R950 instead of the R550 as per the promotion.

Tried to contact them but nobody was willing to assist. Every time I contacted them they said the persons are on leave and I should contact the next day. No responses from tickets and nobody seems to care

Please avoid them