Hi I noticed diesel has been leaking from the fuel cap area on my 2014 octavia, I thought the cap was faulty and bought a replacement from skoda cost £36, after filling up today,  the problem has returned, anyone else had this problem and did you find a solution, thanks in advance. 

Sounds like the full tank is getting pressurised, best to have a garage check the tank vent pipes. 

If the engine is idling & someone revs it, can you see fuel seaping out of the fuel cap?

Maybe best to do it after you've been driving so that the fuel, engine etc are hot.