The problem you are experiencing may be related to calibration issues with the capacitive touch sensor inside the Smart AC Control V3+.
As the Smart AC Control V3+ calibrates the capacitive touch sensors during boot up, the calibration only finishes successfully if the device is not touched during boot up.
If you think that the display may have been touched during boot up then a full reset of the calibration of the touch areas can be achieved by unplugging the Smart AC Control V3+ for 30 seconds. Remember to not touch the screen during boot up.
To avoid this problem in the future, please always place the Smart AC Control V3+ on a flat stable surface such as a table, shelf or a wall before plugging it in.
Generally, it is recommended to cover a larger portion of the touch sensitive area with your fingers rather than pressing the display harder. The blue shaded areas in the image below show the touch-sensitive areas on your Smart AC Control V3+.