Poor service delivery

All was well with the initial first month. Account paid in full for the 120+120 gig a month at a cost of R870. This month however only received 80+80gigs. I called and called and emailed and even WhatsApp but no response whatsoever from no one. No one has taken any liberty of even getting back to me as to why I was short changed 80 gigs this mont as my contract clearly states I’m paying for 120+120 gigs a month. Not impressed with the service from them.