
The only other thing I can think is that it's maybe an issue on the phone settings?
I once had a problem with my Samsung Galaxy Note 4 & my Pebble where notifications suddenly stopped going to the watch.
After playing for hours, it turned out that my phone had decided to save battery life by stopping the Pebble app from running in the background.
I had to go into the phone's power saving settings and set the Pebble app to "never disable"
After that notifications worked fine again, it sure was a mission to track it down!