When you are still having issues, unpair and then repair the Bluetooth devices.

This guides you on how to run the Bluetooth troubleshooter, diagnostics, and general updates.

Perform the steps in the Resolving the Bluetooth Adapter Turning Off section.

Check to see if the latest Bluetooth drivers are installed, for more information see Dell Knowledge Base article How to Download and Install the Latest Dell Wireless Bluetooth Adapter Driver.

If you have not done so already, see The Bluetooth Toggle Icon Does Not Appear in Windows section, to ensure that the Bluetooth adapter is enabled in Device Manager.

See The Bluetooth Toggle Icon Does Not Appear in Windows section, to ensure that the Bluetooth adapter is enabled in Device Manager.

Reset the BIOS to its defaults to ensure the Bluetooth adapter enabled, for more information Dell Knowledge Base article Dell BIOS Updates, see the 'How do I reset BIOS or CMOS and/or clear the NVRAM on a Dell computer?' section.

NOTE: When there is no Bluetooth toggle, it may be caused by one or more issues, see the following resources:

Bluetooth not showing in device manager