Why are some of my Whatsapp chat contact names changed to their phone numbers in my BB Z10?

After the recent Whatsapp update on my BB Z10, some of my Whatsapp chat names were changed to their respective phone numbers. How can I change them back to their names? I made sure all the Whatsapp permissions are checked on and I tried removing and reinserting the battery.

Originally Posted by CrackBerry Question

After the recent Whatsapp update on my BB Z10, some of my Whatsapp chat names were changed to their respective phone numbers. How can I change them back to their names? I made sure all the Whatsapp permissions are checked on and I tried removing and reinserting the battery.

How recent was the update? Can you still view those contacts in the Contacts app? Do you also see them in your "Favorites" list?

The update was 1-2 days ago. I do not see these contacts in Whatsapp favorites and I do see them in BB Contacts.