Hello
Thank you for your question and reaching out. I can understand you are having query\issues related to Windows + L not working.
- Please try to change Keyboard to any other normal USB keyboard or Non-Gaming keyboard.
- Try to run Troubleshooter Click Start -> Settings -> Update & security -> Troubleshoot -> Scroll down -> Click Keyboards -> Click Run the Troubleshooter
- Disable any Antivirus program or Windows firewall you may have for temporary purpose.
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