Not receiving notifications after iOS 18.2 update on my iPhone

Yup me too, I had the same issue earlier this year (summer 2024) and lasted for a few months. I don't even think it was an iOS update that fixed it so I'm pretty sure it's Apples server side.

I don't know about you, but I'm still getting push notifications specifically from Apple services (iMessage and Mail) but nothing from any 3rd party app.

I contacted an Apple rep on one of their support channels and they insisted I contact the app developer (all of them?) before they would continue support. I've half a mind to just lie say I did to try and get them to escalate it.

There is nothing for Apple techs to escalate. Here is a manual for developers about how to generate notifications→User Notifications | Apple Developer Documentation. Even if you aren’t a developer, it is useful in understanding notifications and how they work.

Some things to consider:

• Notifications require a cellular voice connection (or Wi-Fi calling if it is enabled)
• Apps must be launched at least once to enable notifications from that app, and you must be logged in to the app if it requires login
• Notifications must be enabled for each app in Settings/Notifications after the first launch
• If you are in the (very bad) habit of exiting an application by going to the App Switcher and swiping up on the app’s image that will disable notifications for that app. Exit apps to the Home screen ALWAYS, unless the app isn’t working correctly; NEVER from the App Switcher
• Some VPNs can block notifications, so if you use VPN delete the VPN app AND profile

Restart your iPhone.

same is happening for me. I even deleted and reinstalled some apps and its still not working.

Same here. Restarted and everything, there are still no red circles to notify me which is frustrating for my work and home email boxes.