https://community.endlessos.com/t/raspberry-pi-not-booting-with-endless-os-5-0-0/19863
I am experiencing exactly the same issue as the above post. I am using a raspberry Pi 4 with 4gb ram and a 64gb SD micro SD.
Endless OS 5.0.4 English Full wont boot on Raspberry Pi
Can you please tell us which revision of the Pi 4 you have?