Spark Energy Debt from 2014

Bluke89

I am being chased for a debt from Spark energy that dates back to 2014. On 31st Nov 2014 I moved into a rental with Your move who had a deal with Spark energy provider. I setup a switch to Good energy on 2nd Nov (couple days after moving in and researching how terrible Spark were) I don't have the meter readings anymore as I've moved twice now and this is almost 5 years ago,but Spark have estimated that in the 34 days I was with them I used 2000kw and would like me to pay £296! I am currently paying £55 a month for electric and gas so am glad I got out as soon as I did but also livid at their charges. How can they justify that amount. The flat was empty beforehand for the summer I believe and I think their opening read for the date I moved in is wrong by a long way. It's like they've just plucked a number out, completely unjustified. I might be able to dispute the final reading if I contact good energy and they tell me what my opening reading was with them but there's no evidence (from me or Spark) regarding the opening reading on the day I moved in. I also don't want to pay a 5yr old extortionate charge to a company that ceased trading and want into admin. I'll pay £60 as a gesture of goodwill for standing day rates and reasonable usage but they want £10 a day which I don't think is reasonable. Does anyone have any advice as to how I can dispute this debt chaseup? Thanks in advance