Europcar bad incident at Gatwick

After reading several sites of complaints about Europcar I felt I had to add to this site too.   Please don't even think about using Europcar - especially if returning to Gatwick or if you think you will ever get a reply from admin or customer service EVER.
We returned out car in absolutely the same condition it was picked up but oddly enough the young guy seemed intent on not checking the body work but running his hand around the tyre and lo and behold a small cut appeared.   Then he went round to the nearside and again tried to say in his broken English that something was wrong with it but what he was unaware of was that it was a new tyre as we had got a puncture.  Now we go into the office with him and on the invoice it has written 'ripped and torn tyre' and what was going to be a complaint about the front nearside turns into a new tyre.  Now that was after we explained to the girl on the desk and who kept telling us 'we have no knowledge of you having a puncture' but we had rung Europcar emergency to get it fixed!!!  So they took out the money for the tyre and another amount for 'ripped and torn' which was plainly ridiculous and some sort of scam as others have exactly the same incident at Gatwick (too odd for words).  Now they have taken MORE money out of our account without our permission and will not reply to any emails at all from us.  It's just so stressful.
It has ruined our experience with hiring cars now as we are pensioners.  How stupid when we rent a few months each year and they have lost yet another good customer.   I don't understand the company or how they can keep doing this.
Luckily Europcar in Australia have never been a problem but I can't chance another hire from EUROPCAR EVER.