In this post, we discuss the best ways to resolve your iPhone Contacts disappeared issue. Below are the mentioned steps:-
First of all, close your iCloud account then try to sign in again.
Now, change the the settings of group for your iPhone Contacts.
For iPhone Contacts, Turn off/on your iCloud account.
Check that your iPhone settings id selected as default.
After that, try to recover your iPhone contacts with the help of iTunes/finder backup.
We can also restore your iPhone Contacts wit the help of third party data recovery software.
Read more here:-
https://worldzo.net/iphone-contacts-disappeared/