from this page:
https://konachan.com/post

Just above the word Tags on the left side of the screen, you should see

Hidden Posts 0

If there are hidden posts, then that number will be non-zero. If that is the case check your blacklist. You will find your black list under my account: settings. Remove any tags you do not wish to be black listed (Hidden). If there are no black listed tags, Then I have not a clue...

BTW: You should be logging in with https://konachan.com, not http://.....