Nc30 uk fuel issue

[Shortstock]

Hi guys
Wondering if anyone could give me some help please.
I have a nc30 uk bike that has almost no use I left it and the fuel went a bit off.
Took tank off bit of fuel then great.
Left for few months and thought will start and then put tank back on.
So I put fuel in through the pipe that connects to the tank and it poured out via one of the short pipes (overflow)
Can you advise why that might happen?
Many thanks as i need to get this sorted to sell the bike soon
I have a pic but can’t seen to add to post?
Chris

[magg]

Stuck needle or float. Tap the offending carby with a hammer and piece of wood. If you are lucky the needle/float mayunstick, otherwisw you will need to remove the carby and disassemble.