If you want to align caption then add this
.wp-block-image.aligncenter>figcaption, .wp-block-image .aligncenter>figcaption, .wp-block-image.alignleft>figcaption, .wp-block-image .alignleft>figcaption, .wp-block-image.alignright>figcaption, .wp-block-image .alignright>figcaption {
display: inherit;
}