It can be due to abnormal Bluetooth data on the phone. Try deleting the previous connection records on the device or reset the earbuds by pressing and holding the function button in 10 seconds.
To delete the Bluetooth records on the phone:
1. Android phone: Go to the [Settings] APP on the phone >> select [Bluetooth] >> REDMI Buds 6 >> tap [Unpair] (take the Xiaomi mobile phone as an example);
2. iOS phone: Go to the [Settings] APP on the phone >> select [Bluetooth] >> REDMI Buds 6 >> tap [i] >> ignore this device (take iPhone 15 as an example).