I'm using Oreo on an HTC U11. A few days ago, most notifications stopped appearing in the notifications drawer. I still get the notification sounds and vibrations, but nothing in the tray. It's pretty frustrating as even if I hear/feel it, I don't know which app is sending the notification! I have checked through all 'Sound & notification' settings, and individual app settings, but I can't find anything obviously untoward. I've also checked my DND settings, and it doesn't seem to be the issue. I missed a couple of orders for work, and an important message from my children's school, so would be really grateful for any assistance. Thanks in advance