Hi @7sen Are you using the official charger, check that there is no issue with the cable and that there is no debris or water in the charging port. close background apps, if you have any 3rd party apps installed some of them could be causing an issue . Try charging in safe Mode where they are disabled if the case to try and pinpoint the cause https://www.samsung.com/uk/support/mobile-devices/how-to-start-my-galaxy-device-in-safe-mode/
Sometimes wiping the cache partition can solve charging issues. Temporary files are deleted but data is kept intact. Follow these steps:
1. Turn off the device.
2. May need to Connect To Computer or plug in USB-C Headphones , Press and hold the Volume Up key and then press and hold the Power key
3. When the Android logo displays, release all three keys.
4. An 'Installing system update' message will show for 30 - 60 seconds before the Android system recovery menu options appear.
5. Press the Volume down key several times to highlight wipe cache partition.
6. Press Power key to select.
7. Press the Volume down key to highlight yes, them and press the Power key to select.
8. When the wipe cache partition is complete, Reboot system now is highlighted.
9. Press the Power key to restart the device.
I do not work for Samsung or make Samsung Products but provide independent advice and valuable contributions.
My Device- S21 Ultra 5G ( SM-998B/DS ) CSC= BTU , 12GB/256GB
One Ui 5.0,Android 13 .