s6 stuck on samsung entry screen

[yahiadal]

Hi
While working on my s6 (G920F) it restarts and stuck on the samsung entry screen without being able to turn it off.
I am unable to entre recovery mode but ca enter to download mode where I installed stock rom (android 7) but the problem remains.
The phone stay on until the battery is empty.When put on charger it goes directly to entry screen and stays there.
Any help please.
Thanks
yahiadal