Hi ​@Lleuadwen, 

We're sorry to hear that you're unable to make outgoing calls to landlines on your iPhone 17, especially as mobile-to-mobile calls are working as expected.

Please try the following troubleshooting steps:

• Restart your iPhone
• Ensure you have good network signal (try moving to a different location if possible)
• Turn Airplane Mode ON for 30 seconds, then OFF again
• Check for any iOS updates: Settings > General > Software Update
• Ensure your network selection is set to Automatic: Settings > Mobile Service > Network Selection
• Check that Call Barring is not enabled: Settings > Phone > Call Barring
• Remove and reinsert your SIM (if physical SIM) or re-enable your eSIM
• Reset network settings: Settings > General > Transfer or Reset iPhone > Reset > Reset Network Settings

If the issue continues after completing the above steps, please contact us via Live Chat or send us a direct message through our social media platforms so we can investigate this further for you.

Owethu