I know ther are few posts about this but none specific to my problem.
About 2 days ago I stopped receiving my notifications directly to my device. I can start up the app but will not get my notifications. I have reinstalled, pulled the battery, restarted....everything to no avail.
Check the email address connected to the Facebook account. Is everything alright with the email account (no password needs to be updated, etc)? I've had this problem a couple of times and it was because the account had to be re-validated on my phone.