If none of the above steps work, there might be an account-specific issue.
Go to Settings > Ask a Question in the Telegram app to contact their support team. Be as detailed as possible about the steps you've already tried.
By systematically going through these steps, you should be able to resolve most issues related to contacts not showing correctly in your Telegram app.
Ensure the contacts you're expecting to see in Telegram telegram number database are actually saved correctly in your phone's native address book.
Verify they have the correct international format (e.g., +1234567890).
Last Resorts (If all else fails):
Log Out and Log Back In:
WARNING: Make sure you remember your 2FA password (if enabled) and have access to your phone number for verification before doing this, as you'll need them to log back in.
Go to Settings > Devices (or Settings > Privacy and Security > Active Sessions).
Tap "Terminate All Other Sessions" (or log out of your current session).
Log back into your Telegram account.
Reinstall Telegram App:
WARNING: Similar to logging out, ensure you have your 2FA password and phone number access.
Uninstall the Telegram app from your device.
Restart your device.
Reinstall Telegram from your device's official app store.
Log in and check for contact sync.