The most common reasons you may be seeing the "No Signal" message: The projector and the source device are not connected correctly.

The screen rotation is locked. If a user's touch-screen tablet is having an issue with screen orientation, it could be due to screen rotation being locked in device settings.
If the screen rotation is locked, the touch-screen tablet will not rotate the screen when the device is turned.
This can usually be unlocked in the settings or by pressing a specific key combination. References:
https://www.howtogeek.com/254132/how-to-enable-screen-rotation-on-windows-10/

Calibrating the touch screen is the best action to resolve the issue of inaccurate touch input. Calibration adjusts the touch screen's sensitivity and alignment to match the user's touch. Resetting the mobile device could erase user data and settings and may not fix the touch screen issue. Replacing the LED screen or updating the mobile device are unnecessary and costly actions that may not solve the problem.

To configure the laptop to show both screens, the technician should adjust the monitor display settings. On Windows 10 or 11, the technician can select the Start menu, then open Settings, then select Display. The PC should automatically detect the monitors and show the desktop. If the monitors are not detected, the technician can select Multiple displays, then Detect. The technician can then use the dropdown list next to the image of the desktop to choose how the screen will project across the displays12345.

If a laptop has been returned for a screen repair and the owner insists the screen is broken, but occasionally a faded image is able to be seen in very bright settings on the desktop, the first step the repair technician should take is to ensure the backlight is functioning as expected. If the backlight is faulty, the screen may appear to be broken, but it may only be dim or too dark to be visible