Disable 4G Calling (VoLTE) via Network Settings

1. Open the Settings application on your Fairphone 6. 2. Navigate to 'Network & internet'. 3. Select 'SIMs' and choose your A1 Croatia SIM profile. 4. Locate the '4G Calling' or 'VoLTE' toggle switch. 5. Set the toggle to the 'OFF' position. 6. Restart the device to ensure the modem re-registers on the legacy voice network. 7. Verify the fix by confirming that incoming caller IDs are correctly displayed during a test call.

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