I'm in need of some #help

I'm trying to post an mp3. It's way under the 40mb limit, I've tried it at under and at the specified bitrate, but it doesn't seem to want to attach - it looks like it's uploading, but then there's no media in the post when I press the Post button

Any ideas how I'm screwing it up?
#CosoTips

@66ALW99 I think 40Mb is way too big for CoSo servers to have to store. I thought 10Mb was the limit?

I use Dropbox for this reason and just post links rather than put it on the CoSo server.

@Dane The file itself is only 2.6Mb, so it should still be fine.

The 40Mb limit and 192kbps bitrate spec is from https://help.counter.social/en/latest/posting-content.html

I could post it on YouTube and link, it's more that I'm wondering what I'm doing wrong as the file seems to be meeting the requirements

@66ALW99 🤔 is your file one of these types?

.M4V, .mov .webm

@Dane I saw that page - that's where I got the info around bitrate and file size limits. I've tried mp4 and mp3 versions that should, as far as I can see, fall within those requirements