What to do if the Xiaomi Smart Band 9 cannot reconnect to the Mi Fitness APP?

To resolve the issue, here are some steps as follows:
1. Try removing the Mi Fitness APP and then restart it;
2. Attempt to turn off the Bluetooth on the phone and then turn it back on;
3. Choose the band device in your phone's Bluetooth settings and remove the pairing. Afterward, go back to the APP to start the reconnection process. Confirm the prompt once it appears to finish the connection.