Why did the touchscreen randomly become unresponsive after updating to Android 15?

On August 8, I updated my Samsung Galaxy A14 to Android 15 (One UI 7). Everything seemed fine, but suddenly the touchscreen started to become unresponsive. If the display is on, there is no problem. However, if I turn it off with the side button, when I turn it back on, the touchscreen suddenly becomes unresponsive - the phone is unusable. Only the side buttons work, so I set it to turn on the weather with a double click. However, this brings up a screen for drawing an unlock pattern, which I can't enter at the moment. I have to turn the screen on/off for a minute at a time before it starts responding. I set the volume up button to answer a call, so I can also make calls in that situation, but that's it. I've needed to pay or buy a ticket several times and it was quite frustrating. It's clear that the problem is related to the Android 15 update (it never happened before), but it's not at all clear how to solve it? Maybe a factory reset would help, but I don't have time to set everything up again right now. And it's not even clear if it would help. Please help