Then continue with the other steps to go over your install most thoroughly. Start with Step 4 to turn off Startup freeloaders which can conflict and cause issues, then Step 7 to check for infection the most thorough way, then step 10 to check for damaged System Files. Go over this checklist to make sure the install is set up correctly, optimized for best performance, and any needed repairs get done. You can also use System Restore to get before the problem began, then check for Updates with the Hide Update tool and hide them. If this was caused by Windows Updates then you can check which were installed at Settings>Update & Security>Windows Update under Installed Updates, then uninstall them from the link there, and hide with the Hide Updates tool downloaded from here. Then try pairing again, if necessary run the Bluetooth Troubleshooter again. If these fail try to Uninstall the Driver, restart PC to reinstall. Right click Start button to access Device Manager, locate Bluetooth device (if necessary from View tab Show Hidden Devices), on Driver tab see if Roll Back is available, if not try Update Driver, first automatically, then Browse, then Let Me Pick to try all previously installed Drivers. Install it even if it's the same or newer than the one in Device Manager reached by right clicking the Start button. Try Updating the Bluetooth driver from the PC maker's Support Downloads webpage for your exact model. If this is a mic or headset right click Volume icon in System Tray to Open Sound Settings, make sure the correct device is selected for input or output in the dropdown menu.
Try turning off Fast Startup at Settings > System > Power & Sleep > Additional Power Settings > Choose what Power buttons do > Change settings that are unavailable > uncheck Fast Startup. Try the Bluetooth troubleshooter at Settings > Update & Security > Troubleshoot. Make sure you're pairing correctly as shown here. I'll give all possible steps for troubleshooting Bluetooth in order of priority: I'm Greg, an installation specialist and 9 year Windows MVP here to help you.