faulty samsung s 7

Glo Cell Klerksdorp was my service provider in an cellphone contract.

Head Office close down this branch with out any notice. My Samsung S 7 became faulty and I try to contact Glo Cell Head office for assistance . There call centre took ages to answer the phone and when they answer they only listen and did nt help but just disconnect. I try call them on many times

the samsung is still under warranty and according to Samsung I must send the phone back via my service provider wich is GLO CELL