Receiving push notifications for another user that was removed from my app A friend logged onto their Facebook on my phone with the Facebook app and they also added their Messenger account. I'd open the app and it'd have both of our profile pictures to choose from.

I deleted their account from the Facebook app and Messenger, but I am still receiving push notifications when they start a new conversation in Messenger. 

How do I stop receiving these push notifications?
The easiest thing to do is remove the Facebook and Messenger apps from your device and reinstall them.

To ensure that the settings causing you to be signed in with both users are erased, do a hard reset (hold Sleep + Volume Down [iPhone 7] or Sleep + Home [iPhone 6s and earlier] until the Apple logo appears) between deleting the apps and reinstalling them.