@Mounis: Prior to the phone's power cycle, do you see a notification on screen to warn you that the device is heating up? Are you using the USB cable that came packaged with the phone, along with a genuine Samsung 15W plug adapter?
In the meantime, please make sure to close any apps when not in use via the Recents button in your Navigation bar. Also, head to Settings > Device care > Optimise now (if available) > Memory > Clean now. I also recommend switching off Wi-Fi, Bluetooth and Mobile data during periods of downtime.
@Mounis: For guidance on how to backup your device and restore it to its default factory settings, please take a look at the link below, which will walk you through the process.
If the issue should persist following the factory data reset, then please head to samsung.com > Scroll to the bottom of the screen > Contact us, and reach out via your preferred contact method, and an advisor will be able to arrange for the phone to be inspected and repaired by an authorised Samsung engineer.
