Check whether Contacts are hidden in the Contacts app
Open the Contacts app and pull down to refresh
Go to Settings
Tap your name
Tap iCloud
Turn Contacts on
If prompted, choose Keep on My iPhone
Go to Settings
Tap Apps
Tap Contacts
Tap Accounts
Select each account and make sure Contacts is enabled
Sign in again to the correct Apple ID if needed
Check if contacts are in another account such as Gmail, Outlook, or Yahoo
Go to Settings
Tap Apps
Tap Contacts
Tap Accounts
Add the missing account if needed
Open the Contacts app and tap Lists or Groups
Select All Contacts or all available lists
Check iCloud.com for your contacts
Restore contacts from iCloud.com if they were deleted recently
Go to iCloud.com
Sign in with your Apple ID
Open Account Settings
Use Data Recovery
Select Restore Contacts
Restore from a previous iCloud backup
Go to Settings
Tap your name
Tap iCloud
Tap iCloud Backup
Restore the iPhone from a backup if needed
Restart your iPhone
Update iOS to the latest version
Check Screen Time restrictions
Go to Settings
Tap Screen Time
Tap Content & Privacy Restrictions
Make sure Contacts are not restricted
Check whether contacts were synced from a deleted email account
Re-add the account to bring contacts back
Contact Apple Support if contacts still do not appear