I made an avatar and uploaded it, but I can't find it on my credits

I made an avatar and uploaded it, but I can’t find it in my credits.

You may have used the wrong unity version to upload it.
You should be using Unity 2018.4.20f1

I looked it up at Unity Hub, and there’s nothing but 2018.4.26f1 instead of 2018.4.20f1. Where can I install 2018.4.20f1?

The VRChat docs has links to download it via unity hub or as standalone

Thank you