I cannot receive message and calls made to the Galaxy Watch Active2’s phone number. Why is this?

Depends on Mobile networks setting, you may not receive and calls made to the Galaxy Watch Active2’s phone number.

Please check your settings on following steps ; 

Settings > Connections > Mobile networks.

• Auto on/off :   The Galaxy Watch Active2 to automatically connect to or disconnect from the mobile network depending on the Galaxy Watch Active2’s connection to the mobile device via Bluetooth.
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When Galaxy Watch Active2 is connected to the mobile device via Bluetooth, the Galaxy Watch Active2’s mobile network is turned off to save battery power. Then, the Galaxy Watch Active2 will not receive messages and calls made to the Galaxy Watch Active2’s phone number.

• Always off:  The Galaxy Watch Active2 not to connect to the mobile network. When this option is enabled, you cannot receive incoming calls and messages to the Galaxy Watch Active2’s phone number. If the Galaxy Watch Active2 is connected to the mobile device via Bluetooth, you can receive incoming calls or notifications from your mobile device’s phone number.