I have recently started using a new Ubuntu desktop and it does not come with a Bluetooth adapter. I am using the UB500 from tp-link. After plugging it in I could not see any devices to connect to so I followed Bluetooth scan doesn't detect any device on Ubuntu 21.10. Everything was running fine until suddenly yesterday I unplugged the adapter while the computer was running and from then I am unable to use the adapter.
I tried following the document again but this time it's throwing an error when
~$ modprobe btusb
modprobe: ERROR: could not insert 'btusb': Operation not permitted
~$ lsmod | grep -i bt and: sudo dmesg | grep bt
grep: and:: No such file or directory
grep: sudo: No such file or directory
grep: dmesg: No such file or directory
