My boiler which is a WORCESTER 24i JOUNIOR the pilot light has gone out and the warning light keeps flashing and i have pressed and held it in till it stops and have been doing this every time it flashes and i have turned it off and left it off for a while and turned it back on still flashing pressed and held it till it goes out then it comes back on what else can i do to get my boiler to reignite thank you Tez