I'm unable to download animation with audio to Instagram.

Hi there everyone

I made an animation in Illustrator and then took it into Express to animate the different layers and added some audio. I'm pleased with the result.

Now, I can't download it to my Instagram account.

I've looked through other posts to see any answers:
My Instagram account is a business account

I've clearer browsing data

I get an email saying ...........

Hi Emily,
We couldn’t publish your post. But don’t worry, you can fix this in just a few clicks.

What few clicks are those?!

Can anyone please help me with this please?