Turn on Wi-Fi and Bluetooth on both iPhones
Keep both iPhones unlocked and close together
Make sure both iPhones are signed in to iCloud
Make sure the Apple ID of the receiving iPhone is in the sender’s Contacts
Connect the sending iPhone to the Wi-Fi network
On the receiving iPhone, open Settings
Tap Wi-Fi
Tap the same Wi-Fi network name
On the sending iPhone, tap Share Password when prompted
Wait for the password to be shared
Tap Done on both iPhones
If prompted, restart Wi-Fi on either iPhone and try again