Clamping fines

[al2mk]

Car parked on land on a SUNDAY. No residents only parking, no deliveries to the shops that day, not obstructing anyone - the ambulance was not called as I was on St John duty that day. Have since looked the company up on the SIA website and they are unregistered. They failed to check that the car belonged to me etc. Offered no photographic evidence that the car was clamped first or how long it was clamped for. Taking them to the small claims court. How best should I 'word' my claim.