Phone went for repairs but still not back!

I bought a Nokia phone on the 7th of March 2019 at Pep Stores in Trompsburg. I experienced problems with the phone to an extent I took it back to the store on the 14th or 15th of April. The gentleman who was assisting me said they will take it back the phone and said I will have it back after 4 weeks. I've been going back on forth but I still haven't received my phone. I'm not pleased at all with this as I paid the phone cash and my old phone is giving me problems hence I bought this one. It's either I get a new phone or I get my money back in full so I can go buy myself another phone elsewhere.