Happened to me recently as well, i was using the phone while charging and it showed almost 3hour and more of charging time. But as soon as i cleared all apps, did a restart, everything went back to normal.
We acknowledge your query and apologize for the inconvenience caused to you and will surely assist you regarding the same. We would request you to register your concern in Samsung Members Application. So, our concern team gets back to you as soon as possible.
Please follow this path to register your concern in Samsung Members Application (Open Samsung Members Application > Get help > Send Feedback > Error report).
Note. please attach the error log file within 15 minutes of the error occurring.
