MARWOL3, I can see why you're reaching out for some help. Service indoors can be a challenge. There are many factors outside of VZW’s control that can contribute to indoor performance. Coverage can be affected by the materials of the building you're in, local terrain, and other variables.
One solution that can help is Wi-Fi Calling. When you use Wi-Fi Calling, your internet connection acts like an internal cell tower. When you place a call, it will route it to our network from inside your home. To learn a little more about Wi-Fi Calling here's its FAQ page: https://www.verizonwireless.com/support/wifi-calling-faqs/
It's never a bad idea to get a new phone like the S9, as it has expanded capabilities and new features compared to the S7. However, the S7 can use Wi-Fi Calling already. Here are the steps on how to activate it: https://www.verizonwireless.com/support/knowledge-base-203686/
Let us know if you have any further questions on Wi-Fi Calling or the S9.
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