Cellphone Repair

I sent my cellphone in for software repairs over 2months ago as it was still in warranty and to date i have not received it bac. I have been to the store on several occasions and called but kept on being told that they were waiting on the supplier, i have tried to call the supplier as the people at the store were not able to assist with this and was told today that i have to pay an additional amount of R+-300 whereas on taking the cellphone there no one bother to tell me this information. I am very unhappy as i am still expected to pay for a cellphone contract with no phone in my possesion