Filling T350 with petrol

[Whizz65]

Have had TVR's for a number of years and there're not the easiest of cars to fill with petrol.
However the T350 (which I’ve had a couple of weeks and love) sprayed petrol out when I opened the ball valve this morning, it’s a pig to fill but I can live with that.
It was a hot day and I opened the petrol valve very slowly and it started to spray out, obviously I shut it and put a paper towel over it but quite a bit of petrol came out. The gauge was showing 12 litres.
Anyone else ……….. someone must have the same problem? Any suggestions?
Many thanks