Make sure you're using the correct account in the SDK
The most common reason we see for missing avatars after an upload is when users may have uploaded to the wrong account entirely. We recommend making sure you verify this before uploading to the account and then verify it when you sign into your account to locate the avatar.
Are you sure you’re logged into your VRChat account?
Please select “Logout” in your System menu and then log back in using your VRChat account. Note that platform accounts (Steam / Oculus / Viveport accounts) cannot upload or use custom avatars (but can use avatar pedestals).
Are you using the right Unity version?
You must use Unity 2019.4.31f1 as described in the VRChat Documentation. Any content uploaded from a newer Unity version will not be visible in menus.
I've lost access to my avatar entirely and need assistance in recovering it
Unfortunately, we are not able to provide users with files that have been previously uploaded to VRChat. We recommend keeping secure backups to avoid any losses of personal data.