I also have this same issue. Since updating my Tapo C100 to firmware version 1.1.9, the notifications have totally stopped working. Both push and in-app notifications are affected.

Motion detection still triggers automatic recording so I can confirm that still works, it is just not notifying at all.

@Leah96xxx 

Me too, I had no problem regarding the local recordings and triggering. 

So...after many reboots of camera and modem/router,the solution to the problem was to remove the cameras from the application and "marry" them again with the modem/router.

Hope it helps:)