At the bottom of the capacitive touch screen, the touch became difficult to recognize and higher than necessary. Why can this be so?

Question

Android

There is a Chinese Android phone with a capacitive screen. At first, the touch buttons began to be pressed with difficulty, as it turned out, it was necessary to press a little higher and it became normal. But now it has become so that at the bottom of the screen, it does not respond to pressing, for example, if you pull the top where the clock is down, then close it with an upward movement, it is not always possible to catch on this part, you have to do it with the back button.
I put a program that shows a dot when you press it with your finger. The multi-touch works, everything is fine from the top around the edges, where I click there and it is shown, and about 1 cm from the bottom, if you move from top to bottom, then the point moves more slowly and remains somewhere 5mm higher, although the finger is already on the edge almost touches the buttons. That is, the inaccessible zone from below is about 5 mm (but it changes, more on that below). When you click there (it should be noted with difficulty), it is pressed higher. For example, it can be done with the thumb (although it is pressed higher), but with the little finger it does not work at all, although everything above also works from the little finger.
It is also noticed that if you rub your finger at the bottom of the screen, then the place of pressing decreases, that is, you can even hold one finger in the program, move the other from side to side and see how the point decreases. By the way, in the same lower part, if you hold your finger and press anywhere with the second, the point also drops by 10-15 pixels, and when you remove the second finger, it rises again. That is why it is possible to pull the strip with two fingers (since the area below is obtained), but with one it does not work if you do not rub it from side to side ...
Tell me, please, what could it be? I dismantled the phone, didn’t notice anything special, cleaned it from dust, assembled it, it works as it did, that is, it didn’t rise, I tore off the film, it turned out to be in vain, everything is exactly the same ...

Answer 1

As already mentioned above, a similar problem was on HTC Hero. I was the owner of this device, and suffered with it. Over time, the problem grew into something like this:

As a result, this article helped me: habrahabr.ru/post/129098/
After warming up, the phone still lives.
I think you have a similar problem and you should try this,

Answer 2

Most screens suffer from this over time, take a cheap new Chinese android phone for 200 bucks and live on.
A similar case was with htc hero

Answer 3

In principle, you can try to replace the touchscreen yourself, and buy a non-branded one.
When my wife had the same problem, I became interested in fixing it myself - both experience and savings. It turned out 100 rubles. per touchscreen + 2 hours of personal time (including searching for instructions).
In principle, the main thing is to do everything carefully. It's been a couple of months since I replaced it and everything is fine. Just in vain I put double-sided tape - it would have held on like that, but now I have to press a little harder.

Answer 4

I would not advise changing the screen to a new handicraft. In my personal experience, I broke the screen on Apple four times. Three of them changed glass for the promised "quality copies". In the end, nothing good came of it.
On the fourth, I replaced it in the official service center with the original. But for the price it turned out that for the same money + to sell a battered one, you can buy the same model, only a new one.