Cell C
Refusing to repair phone

I sent my phone in for repairs in October they told me i could come on 11th or 12th of January because it would still be under warranty, even when I checked in the phone on the 11th I asked them to confirm if it was under warranty and it was. Now they say I must pay R1000 to fix the phone, when I tell them the story no one is taking responsibility and they telling me I was given the wrong information, whats infuriating is I've been with Cell C since 2005 have had two different contracts with them and now this is how they treating me