Shocking service levels from MTN

Shocking service levels from MTN. Dependant on my mobile phone for customer calls, my MTN service is fluctuating. I don't receive incoming calls (without indicating a missed calls) - neither can I dial out. Battling for help since February 2020. Despite 11 visits to MTN Garden Route Mall, George, several calls to call centre where they reset my phone, check my settings, buying a new sim card, sending my 4mth old new Iphone 11 away to MTN in PE to check the device (which took 9 weeks) - I have less connectivity than 4 months ago. MTN Garden Route Mall in George promised so-called CCMS investigation 5 days ago - still completely missing in action. My monthly contract, however, gets debited regularly although no assistance to resolve my urgent call for help. Losing money due to no connectivity. Only whattsapp telephone calls working perfectly. Cannot even call MTN customer call from my Iphone! Geniunely desperate for action and service from MTN