Excuse me Sir, my gif has been taken off the fun stream front page for apparently being a "repost" while other meme do the same thing. Can you do something about it?

Unfortunately I don't have the ability to reverse a disapproval, unless the image is in my approval queue and I'm the Moderator taking action on it.

One way to help avoid your submission being disapproved in the future is by adding your own unique spin on the idea by adding your own unique text, drawing, or stitching it together with other images.

I made this Public Service Announcement a couple years ago before I became a Moderator, still true today: imgflip.com/i/22k7ta

Alright thanks.
But then Shouldn't most of the gifs in the front page be removed because most of them don't have captions.

You're welcome.

"But then Shouldn't most of the gifs in the front page be removed because most of them don't have captions."

Maybe you misunderstood my advice.

Some users take advantage of the options available in the Gif Maker to add a creative caption or image to their gif's. Adding either or both of those is not a requirement, but it probably helps.