In Xiaomi/Oppo devices, there is an extra layer of security that you need to enable in the developer option in order to connect your device and work with TestProject.
Enable the "USB debugging (security option)" option. To do this, you will need to have a SIM card in your device.
Enable the "Install via USB" option
Try going to the device settings and Disabling Permission Monitoring.
If none of the above helped you, try to disable the "MIUI Optimization" option
If none of the above solutions helped you, please contact us in the chat. We would love to help :)