Misleading

In October I upgraded to mtn my data package for R299 80GIG 2 line packages. I received my invoice was supposed to be R887 per month as agreed, but Mtn debited my account with R1532. When I enquire I was told credit was pass on late so I will received my credit in December. The issue I have was that it was the same thing in October I had to call in. Mtn no longer provides us with statements.