Hi Masoud,
Welcome to Microsoft Community.
I'm Hahn and I'm here to help you with your concern.
I'm sorry to hear you're having trouble with your Surface Laptop 7th Edition's touchpad. A few users reported that the touchpad stops working when plugged into a USB-C power source. If this occurs, unplug the USB-C power source, after which the touchpad should start working again.
If this is not the case for you, Let's try a few steps to see if we can resolve the issue:
- Force a shutdown and restart your Surface: Force a shutdown and restart your Surface - Microsoft Support
- Run the Surface Diagnostic Toolkit: Fix common Surface problems using the Surface app and Surface Diagnostic Toolkit - Microsoft Support
- Confirm connectivity: Press the Caps and Fn keys on your Surface Type Cover or Keyboard several times to check whether the LED lights turn on.
- If the LED lights turn on, your problem may be with Windows and not the device itself. The next step is to reset your Surface. Here's how: Restore or reset Surface for Windows - Microsoft Support
- If the LED lights don't turn on, there might be a hardware issue. To verify in UEFI, do the following: How to use Surface UEFI - Microsoft Support
Press the up and down arrow keys to change what is selected on the left side menu to check if the keys work or not.
- If the keys are working correctly in UEFI, but not in Windows: The problem is likely with the software installed on the Surface, and you'll need to reinstall. See Creating and using a USB recovery drive for Surface .
- If the keys are still not working correctly: If the Type Cover or Keyboard still doesn’t work on your Surface, submit a service order for your Type Cover or Keyboard.
I hope this helps. If there is anything not clear, please do not hesitate to let me know.
Your Sincerely
Hahn. W - MSFT | Microsoft Community Support Specialist