I have fixed all the problems (notification and download stuck google play store) !!!!!!    The solution?   For anyone still having problems with downloading apps while Bluetooth is enabled, I might have found the solution. It seems that devices that have once been paired with your Android device may be attempting to reconnect with your phone even after the device has been removed from your Android device. This seems to cause issues with Bluetooth which in turn causes many issues on your Android device, such as downloading apps. I haven't had the issue return as of yet, crossing my fingers that this works. I stumbled across this solution when reading posts in other languages where a Logitech device using Bluetooth kept attempting to reconnect to a previously paired Android device which caused the Android device to have random issues like not being able to download apps from three Google Play Store. Sure enough, there was a headset attempting to connect to my device repetitively. Disabled Bluetooth on that device and it fixed my problem.   Try this and see if you are able to track down a device attempting to connect to your Android device then disable Bluetooth on the device you find.   Step 1: Download the nRF Connect for Mobile in the Google Play Store (it's free, not my app) Step 2: Enable Bluetooth and open the nRF Connect app you just downloaded.   Step 3: Press the Scan button at the top right, if the scan does not automatically start.   Step 4: Look next to the Advertiser tab, when a device attempted to connect to my Note 10+, it opened a new tab with the device name. I cannot guarantee that it will always show the device attempting to connect or the device name. I may have gotten lucky.   Step 5: Disable Bluetooth on the device attempting to connect to your Android device.   Step 6: Restart your Android device and try downloading an app from the Google Play Store. Please let me know if this sollution works for you. I'm very curious.   Disable Bluetooth and restart the Mobile.    ... View more

Uninstall Google APP, and it will fix the problem! ... View more

Settings-> Devide Manager -> Battery ->  Settings --> Disable "optimize settings" and Reboot the device. Try it! ... View more