There are a few things to check if you experience this:
Wiring Check
- Turn your Raspberry Pi off. Remove and re-connect the ribbon cable to your Raspberry Pi DSI connector. A slightly loose ribbon cable is the most common reason for touchscreen issues!
- Make sure you're only using two of the GPIO wires to pass 5V and GND to the display
Power Supply
Make sure your power supply does function
Raspberry Pi OS (+ Updates)
The display only official supports Raspberry Pi OS. If you're using a different/custom OS we can't guarantee the display won't have issues - so it's best to troubleshoot with Raspberry Pi OS.
It's also wise to make sure your Raspberry Pi OS is up to date. You can do this by opening a new terminal window and entering the following commands:
sudo apt-get update
sudo apt full-upgrade