Can't dial 087 or 086 with your airtime available

This has to be the most useless cellphone service provider. I have over 400 airtime minutes but cannot dial numbers starting with an 086 or 087, which means I can't contact my bank, insurance, medical aid etc. On querying this I was informed that I need to buy airtime in order to use what they term "premium numbers", which I then did through their own app, only for it not to work and then be informed after the fact that I need to purchase airtime from a store and get a voucher in order to load minutes, and the airtime that I just purchased Through THEIR OWN APP will only be added to my free minutes.