i have managed to have a look at the beak myself now and it's not a crack more like a splitting at the tip of the top beak in layers. He may have always had it and we have only noticed now because he is under the weather. he is sat under my chin now and he just let me pick him up and take him out of the cage.
Last night I gave him some chit chat which he loved and had no problem eating it, also cucumber and tomatoe. He just won't stop nesting up to us and when he is in his cage he is just sleeping and he has never been like this before.
He is not shedding any feathers which they normally do at this time of year don't they?