Hi!
Based on the issue you described, it seems like there might be a problem with the USB connection or the phone's battery. Here are some troubleshooting steps you can try:
1. USB Cable: Make sure you are using a good quality USB cable. Try using a different cable to see if it makes any difference. Sometimes, faulty cables can cause intermittent connections.
2. USB Port: Try using different USB ports on your computer. Sometimes, the USB port you are using might be causing the connection issues.
3. Battery: If your phone's battery is very low, it might not have enough power to stay connected during the flashing process. In this case, try charging your phone for a while before attempting to flash the firmware. You can also try using a different power source, such as a wall charger instead of the computer's USB port.
4. Drivers: Double-check if you have installed the correct drivers for your device. Uninstall the existing drivers and reinstall them again to ensure they are properly installed.
5. Flashing Software: Make sure you are using the correct flashing software and the latest version. If you are unsure, check the official forums or website of your device manufacturer for the recommended software.
If none of these steps work, it's possible that there might be a hardware issue with your phone. In such cases, it's best to contact the customer support of your device manufacturer or visit a service center for further assistance.
I hope these suggestions help you resolve the issue with your Redmi 6A. Good luck!