Phone calls showing up on MacBook Pro, but not on iPhone

Hi,

Whenever my MacBook Pro is around my iPhone, whatever incoming calls I receive will show up on my MacBook but my iPhone has absolutely no response. There was even once where my MacBook was closed, but the incoming call still didn't show up on my iPhone, leading me to believe even when my MacBook is sleeping it will still be the only receiver for calls. The only thing I have done so far is turn off Wi-Fi calling on my iPhone. As far as I know, calls are supposed to show up on both devices.

Please help troubleshoot.

MacBook Pro 2015 Model running macOS Mojave

iPhone 6s running iOS 12

Thank you.