Hi @Simmoni, I am sorry to hear about this.
Your post has been translated to English as this is an International forum, please post any replies in English and it will be easier for me and other users to assist you.
Do you have any kind of screen protector mounted on your screen and if so, have you tried taking it off to see if the response is better without it? Also, have you been able to carry out a quick test of the touchscreen in order to see if the touch screen responds as intended? In order to do this, find and tap Settings > Support > Xperia Tests > Touchscreen
Another thing that you can try is to reboot your phone in safe mode to see if the touchscreen works better there. All apps downloaded from Play Store is temporarily deactivated while in safe mode and by doing this, you can see if this behaviour is caused by a downloaded app. For more information on safe mode and how to use it, click here.
Try these measures and let me know how it goes!
