Help with iPhone 4 - not receiving notifications

Dec 22, 2011
I recently jailbroke my iPhone 4, and since then it won't receive notifications for apps such as whatsapps, twitter and facebook. This has started to get really annoying - especially with whatsapps as i have to keep refreshing to see if i have received anything.

It may be nothing to do with the jailbreak because it could have happened just before it or after which is unrelated.

Does anybody have any suggestions to fix this?

Thanks, Mike