Hey there jaclyn1966,
Thanks for reaching out to Apple Support Communities. I understand your contacts are empty after updating iOS. I’ll be happy to help with this.
You mentioned trying to import the vCards from iCloud. It sounds like the Contacts show as expected in the iCloud website and other devices. If this is accurate, go to Settings > Your Name > iCloud on your iPhone and turn off Contacts. Restart your iPhone using these steps:
Restart your iPhone, iPad, or iPod touch
Turn Contacts back on after restarting and see if they look as expected. If not, go to Settings > Your Name and tap Sign Out at the bottom. Restart your iPhone after completing the sign out process and then sign back in.
If that doesn’t help, back up your iPhone and reinstall the latest update with these steps:
How to back up your iPhone, iPad, and iPod touch
If you can't update or restore your iPhone, iPad, or iPod touch
Let us know if that helps.
Cheers.