Dear Samsung Member,
Greetings from Samsung Customer Support!
Please perform the below mentioned steps to resolve the issue:
1. Check connectivity
Please check whether the charger cable and adapter is fixed well. Remove charging cable and reconnect with mobile phone properly.
2. To improve recognition performance, register fingerprints of the hand used most often to perform tasks on the device.
For further assistance, register your concern in Samsung Members Application (Open Samsung Members Application > Get help > Send Feedback > Error report/Ask questions).
Thank you for writing to Samsung.
Samsung Customer Support