Extemely terrible service

I purchased an iPhone last month, and its been faulty from the get go, I went back to the store thrice, with 3 different store managers who kept telling me to come back the next day or the following week, I eventually couldn't take it anymore and asked for a refund, they made me clear the phone , took it back, then told me they cant process a refund immediately as they don't have cash on hand. I am now sitting without a cellphone or my cash , given constant excuses as to when I would get a refund and unfortunately cannot wait any longer, as I use my phone for work and have already gotten 2 warnings due to the constant issues the phone was giving me in the first place. The staff at incredible connection are not helpful at all, and were extremely rude when I asked for assistance, took 2 hours of my time yesterday, having to travel from Florida to sandton every weekend without assistance has honestly become unbearable. Is there someone I can escalate this to? a higher power perhaps please..

kindest regards Kaashifah.