welcome finance early repayment charges?

[Graham G]

i got a car on finance 6 months ago and because i was new to credit the only finance company that would touch me was welcome finance who had a very high interest rate of 40% but i was desperate to get a car for my new job and stupidly took it up. my credit rating has now improved and my bank has offered me a loan at a rate of 8.9% which means if i use this loan to pay off wfs i would save £150 a month. anyway today i called for my settlement figure and was told that it was £7304 but i borrowed £7240 over 4 years for the car in the first place. i have so far made 5 payments of £280 and have always paid on time and never missed a payment which means that i have so far paid back £1400. in their terms and conditions they state that if i want to pay back the agreement early i would have to pay a penalty of 2 months interest which is about £240 from how i calculated it.
so my question is after paying £1400 of the original £7240 that i borrowed how have they come up with a settlement figure of £7304. shouldn't it be 7240+240(2 mnths interest penalty) - 1400 which is £6080. this is what i thought the settlement figure would be and not the £7304 they are talking about. i asked them how they worked out this figure and they said it was the computer that came up with the figure. how can £1500 be equivalent to 2 months interest.
any suggestions on how i can deal with this. (i know i was stupid to take out finance at such a high apr)