Free Traffic Legal Advice

I was caught speeding in a hire car in Italy in May 2023, with an unexpected fine sent through in Feb 2024. I duly paid it (and have proof of payment from my bank). I thought nothing more and then a year later started being chased for non- payment (May 2025). I sent proof of payment( bank statement from HSBC) promptly but got no response. I have just received a letter from a UK claims recovery organisation claiming I owe £600 in fine and cost. As a point of principle, I won’t pay the fine again. If they don’t drop this, escalate costs and we go to court, what is the likely view of a judge, if I can show a statement with my payment to the correct account. I have communicated promptly every time but return communications have been slow/non-existent.