Router and Bad Service from VOX

I have a bought a router from them and it wasn't working, i call them for assistance and they didn't assist me , because it came with the Telkom sim i decided to call Telkom to request assistance because i didn't know whether it was network or the router Telkom told me that the sim card is not my name , then i sent Vox an email about the whole situation fortunately enough I got a respond then we agreed to to continue with their service as they double debited me and I had to dispute the debit , Friday i got a best call from Vox to assist me when the router working that consultant was friendly and i was happy , the sad part is today morning i received a letter of demand and that surprised me and I'm no longer interested in their services because it will have an negative impact to my credit score. Bad service from the sales department from the point of sale and now i'll rather buy a pocket router and requested them to send me a bill for everything and would like to cancel everything.