Your video is 19.5MB. I compressed to 15.8. Max for 8kun is 16MB I think.
Hmm, not right now, but mebbe steal some later for baking. kek
I download w/4k video downloader, which you should already have a copy of original video you're trying to post on your machine. Alternatively you can download directly from telegram. Nice feature, except downloads as MOV type file? Then upload to compressor, make sure is mp4 format, I don't think MOV will post on 8kun. https://www.freeconvert.com/video-compressor
Reduce size to no more than 16MB and your good to go.