Hi joenor,

This may not help much but it may help to find the cause of erroneous touch screen response.

If I'm not wrong, your VK world phone uses Android Lollipop. I'm using KitKat 4.4.2 so it maybe different. In anycase you need to find "Show touches" option. In KitKat, this can be found in Setting-> Developer Options. Scroll down and you will find "Show touches". Just check the box next to it.

Now you can touch any part of the touch screen and see if it registers correct touch location.

you can check the following:

Did you (before the problem first appeared) ever:
(1). Connect a power bank to the phone and hold both together in your hand as you walked.
(2). Use your phone in wet conditions like in the rain or with wet hands.
(3). Place your phone in a tight bag with hard objects without some sort of protection such as phone casing.

If you answered yes to any of it, some damage related to screen sensor may have happened.

You may try the following advices, but avoid risky methods that may ruin your phone. Use warranty if it is still valid. Some are software-related but most are unfortunately hardware problems, where screen replacement is necessary.

http://www.smartmobilephonesolutions.com/content/how-to-fix-the-touch-screen-on-an-android-cell-phone