Hello, my iPhone screen is malfunctioning. It is responsive even if I don’t touch it. What may be the cause of that snd how can I fix it ?.

Hi, Roger6040 and thanks for reaching out on the Apple Support Communities. We see that you're having issues with touch on your iPhone. We'll be happy to go over some possibilities of the cause.

From our "If the screen isn't working on your iPhone or iPad" article:

"If your screen is too sensitive or responds intermittently to touch

1. Restart your device.
2. Make sure your screen is clean and free of any debris or water.
3. Disconnect any Lightning or USB-C accessories. If your screen works after removing an accessory, try using a different outlet, cable, or charger.
4. Remove any cases or screen protectors.

If part of your screen doesn't respond, responds intermittently, or responds even when it's not touched, contact Apple Support for your iPhone or iPad."

Step 4 would indicate you'll likely need to have your iPhone repaired.

We hope this helps out.

Take care!