Sold a Faulty phone , and bad service in terms of repair!!! WANT Service promised or FULL REFUND!

I am very disappointed in the service I have received from PEP. On 27th of May I bought a AO3 Core, cash purchase. On 27th June I returned it as the phone was faulty and would not start as it just kept restarting. I booked the phone in with Nontobeko the store manager who advised me that the phone would be picked up the same week. I called this morning (12th of July) to check up and I was advised the phone was only picked up by technicians on 10 July.

I am frustrated as it is used for work and I have paid the money upfront to receive such shocking service. I want my phone back ASAP or money returned. I was sold a faulty phone and I want a refund or the guarantee to be carried in a professional manner. The phone cannot sit for 2 weeks in store after being booked to be fixed. This is ridiculous!