ive just recevied a claim form from lowells for an old debt that is showing as default in 2009 ive got no means to pay the amount requested as im already struggling to pay my bills and am three months behind with my mortgage please help where do i start?

Hi , Im new to these forums and really need some guidance on were to go with this matter. In 2010 i took out a mobile phone contract with orange the contract was for a iphone as far as im aware , after a few problems i returned the handset was within the 7 day period, i then tried 2 more handsets and couldnt settle and returned these, as far as i remember the contract would have been a 18 month contract at £35.00. My problem is after returning these handsets i moved 2 months later . had mail redirected for 28 days and in this time dont remember recieving anything inregards to this. Anyway the debt as now been passed over to bryan carter and court documents have been recieved. i want to defend this debt. Bryan carter are telling me a payment was recieved for £89 ( i think this may be a credit actually from orange on to the account for the delivery fees - and the partial months - How do i find out if this is the case? . Also bryan carter are telling me the debt was sold to lowell in 2011, its now 2013? . If id taken out a contract for 18 months - The balance would be £630 , If it was 24 months £840. this doesnt include termination fees and there others fees?? The balance is £276.19 - without court fees. This doesnt make sense? Even if i add the £89 theyve recieved were does this amout come from? (£365.19) . Can anyone offer any advice on how i procede with this. All correspondence recieved so far is also for my new address (been here nearly 3 years) . No one as ever mention my previous address . I moved here january 2011 . Really stuck at what to do but dont wanna end up paying for something im sure i returned. Thank You in advance