Beaglebone sd card flash does not boot up

[Nick]

Dear forum

I used on one your prebuilt image from this link https://beagleboard.org/latest-images

i have use the one with sha256sum: da97d7794d834ee785265162635aedcca80fd6dc374593dd05473c0a25f0ac73

flashed on the sd card using the command given in bellow sudo dd if=/path/to/downloaded.img of=/dev/devicenod and then i remove power plug press the boot key(S2) and then plug the power plug

but the BBB does not seem to boot from sd card why?

REgards