The Xiaomi Redmi 9 Prime was officially released on August 4, 2020
The smartphone is equipped with sensors such as a fingerprint sensor (rear-mounted), accelerometer, proximity, and compass. The smartphone features an Infrared port, USB 2.0, Type-C 1.0 reversible connector, USB On-The-Go, and Bluetooth 5.0.
Sounds like the touchscreen is ‘ghosting’ this usually occurs with a damaged flex to the screen digitiser. Not a lot you can do but replace the screen again.
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