Does the data from your Huawei Y9 (2019) tend to get lost, or the buttons or other parts start to break, or the screen turns on and off constantly?
This may be because the phone's flex cable is defective.
The flex cable of your Huawei Y9 (2019) Side Key is an important part, because it connects various connectors and parts of your phone. The flex cable can breake on the flip and slide phones, but also on the newer smartphones.
The price for this repair includes labour + Huawei Y9 (2019) Side Key flex cable