My backup is not showing on my iphone 8plus

Did you read through the articles? They can help you solve your issue. There was one piece in the second article that seems most relevant to your issue:

”If the backup you want to restore from doesn't appear on the Choose a Backup screen

1. Confirm that you have a backup available.
2. Try to restore your backup on another network.
3. If you still need help, archive important data then contact Apple Support.”

Please let me know how else I can help.

Chance

Hi!

These two articles may help!

If you can't back up to iCloud - Apple Support

If restore from iCloud backup failed - Apple Support

Let me know if there’s something else I can help with!

Chance