Baxi instant 80 he fails to light?

hi
my baxi instant 80 he combi boiler fails to light.

i reset the heater, it lights for a couple of seconds then cuts off. after it has cut off the flame failure or blocked condensate drain warning light starts to flash.

i have taken the front off the boiler and noticed the condensate trap was full, i have emptied the trap but this has had ne effect and the boiler still fails to light.

could anyone help??