On the Steem platform you still need to provide a reference. This is because content is monetized. Also, you've used the #photography tag. Using that tag indicates that you are implying that you are the photographer. Although the post is about photography, the implication is there and is specific to the Steem community.
Going forward, always add reference links, even if the images are Creative Commons and use the #photography tag for photos taken by you.
I wish you would have told me this before you downvoted me. I lost so much of money. Being discouraged, I have completely stopped using images and photography tags in my posts.