no flowers on top half of forsythia

hi, does anyone know why my forsythia does not flower on the top half of shrub please? i prune it each year after flowering. any ideas how to rectify this? its 10 years old. thankyou.

this forum now has me down as a serious gardener, this is not what i registered has. cannot see how i can change this now. i think the change over of the forum has changed things it should not. never mind.

 

Crocus. Forsythia flowers on last years wood. So you need to prune it straight after flowering and then leave it to grow new flower buds for the next year. If you pruned the top late last year you will have cut off all the new flower buds.