Can you describe more? Are they just not showing up? None of them show up or is it just some of them?
Notifications come strictly from your Public Inbox relays. So, it might be that some people are not sending posts to the right place you want.
Or is this about Push Notifications?
Also, do you have multiple users logged in? I am currently investigating a bug on user switching back and forth. If this is the issue, then if you go to Phone Settings / Apps/ Amethyst / Force Close, start again and don't switch.. the notifications should work.