I encountered the same problem, building a linux/amd64 image following the official AWS tuto.

I finally succeeded to create a (working) lambda function using the one of the 3 images published in the ECR repro : not the one with the tag mentionned in the "docker push" command, not the one with size 0 but the 3rd one using its hash tag.

I don't know why the "docker push" command generate 3 images in the ECR repo ! and why the image tagged in the "docker push" command is not working...