That's nonsense.
You never said it was NOT your work and were happy to accept praise for the work of others.
I searched but couldn't find any credit or photographers names.
But that's irrelevant.
I posted the first rule of Instagram earlier. It says:
- Share only photos and videos that you’ve taken or have the right to share.
As always, you own the content you post on Instagram. Remember to post authentic content, and don’t post anything you’ve copied or collected from the Internet that you don’t have the right to post.
That others are reposting doesn't give you the right to also steal others work.
Your suggestions that
If they don't want people to repost their content, they will #1 say something like '' don't repost '', #2 they will contact the person to remove the post or passed their account in private. ...
.. are completely invalid.
Copyright belongs to the creator of the work and it's not up to the creator of the work to prevent you stealing it.
Many times they won't even know it's stolen so cant contact the image thief to request it be taken down.
I've been the victim of people like you who used the same excuses.