VisionFive 2 refuses to boot any image other than sdcard.img

Maybe it is an anti-spammer block, probably a limit on the number of posts you can create. I checked your account and it has “Joined 2 days” and 9 posts created. My guess is give it 1/6/24 hours and you will be able to post more and the limit will increase or go away over time, maybe do the tutorials might get you more posts (proves you are a human and not a bot).