Overdrawn a little - charged a lot!

foximus.prime

Hi, I was wondering if anyone could help me out. Myself and my partner have a joint current account with Santander (not for long, I assure you!). We had a lot of financial trouble a while ago where we kept going overdrawn, with a long period where we had to pay £25 standard monthly charge, plus a £15 charge for every 'instant overdraft request fee' we had. (Note: this figure seemed to chop and change from £5 to £25 for some reason) We finally dug our selves out about 8 months ago and things have been fine until now. My other half used the card to pay at a garage because he said he knew there was over £10 in. Unfortunately, the money didn't come out of the account until a week later at the same time as another purchase came out which was made 2 days previously. This resulted in the account going overdrawn by a massive £8.66! Now we are being asked to pay a total of £40 in charges! He called Santander who said they would remove £15 of the charges but we still have to pay the £25 monthly fee. About a year ago during our previous problems my partner called the bank and during this conversation he was told that they try to be fair on customers and that they allow you 2 days to rectify the account, to allow for 'accidents' (he mentioned this in the recent call and has now been told thats not true). Anyway, the reason i'm annoyed is because the day after we went overdrawn money went into the account, so we were only overdrawn for about 24 hours. We are only just keeping our heads above water at the minute and it may only be £25 we have to pay but we just don't have it.
Any advice would be appreciated!