I have provided some information below that may help.
Step 1. Complete a soft reset.
- Power the device off
- Pull the battery out for 20 seconds
- Place it back in
- Power the device back on
Step 2. Ensure the contact names match the Facebook friends names (no nicknames are being used etc.)
Step 3. Try logging out of the Facebook application.
- Open the Facebook application
- Press menu on the main page of the Facebook application
- Choose Log Out
Step 4. Log back into the Facebook application.
Step 5. (If the above steps did not work) Remove the Facebook account.
- Press Menu
- Select Settings
- Select Accounts
- Select the Facebook account
- Select Remove account
- Confirm Removing the account
Step 6. Add the Facebook application back and ensure it syncs over the information.