Send a letter before action – essentially a letter saying I’m going to put in the claim in 7 (or 14) days or else. There are loads of templates for them online. Make sure it says that it is a letter before action and says that you’ll start court proceedings without reference to them.
Assuming they don’t pay it within the 14 days, then once you put in the claim and pay your £35, they owe you it, assuming they admit that they owe you the money in the first place, or you win the court case.
Assuming you’re a person not a business, then going to court is not the end of the world – firstly, if they pay you back the original money, they have admitted that they owed you it. This way they can’t defend the court claim. Then they have a choice of either a)paying you the £35, or having a CCJ against them, which is a pain both for a business or an individual (means you can’t get mortgages etc.). For £35, only an idiot wouldn’t pay it.
Also, when you say £35, is that for a claim on Money Claim Online – if not, it is cheaper to do it on there.
If he pays the sum owed and not the court fees you probably don’t get the £35 back. Unless you are prepared to go to court for just the £35.
Although, in these circumstances, he is very unlikely to be able to defend the case if you do ‘go to court’, because he clearly did owe the money, given he admitted it by paying it, so ‘going to court’ only means filling in some forms on money claim online, it won’t be a hearing or anything.
Joe