Thank you for sharing your concern. We acknowledge your query and apologize for the same. And please follow the easy troubleshooting steps which might help to solve the issue.
Network mode should be set to LTE (Auto-Connect) 1: Set the networking mood- Path: Settings > Connections > Mobile Networks > Network mode SIM1/ SIM2 LTE/ 3G/ 2G/4G (auto connect).
2: Reset the network settings- Path: Settings>General Management>Reset>Reset network settings
In case the issue still occurs. Please register your concern in Samsung Members Application (Open Samsung Members Application > Get help > Send Feedback > Ask question).
Thank you for writing to Samsung. Warm regard, Samsung customer support
