Hey MrsPriceKnits,
Thanks for using Apple Support Communities! I understand you iPhone isn't ringing, or showing that a call is incoming since updating. I definitely understand how important it is that you're able to get calls on your iPhone, and I'm happy to help.
You mentioned that your iPhone is on the latest iOS, I would like to double check that. There has been an iOS update of iOS 13.1.3 released, and this does address an issue that could prevent a device from ringing or vibrating for an incoming call. If you're not already updated, please see the steps on how to do that here: Update your iPhone, iPad, or iPod Touch
Is this happening with all calls? If this is only with calls not in your Contacts, I recommend you also check Settings > Phone and see if "Silence unknown callers" is enabled there.
I also wanted to share the resource below with you, as this goes over some great information non receiving calls on your Mac.
Make and receive phone calls in FaceTime on Mac
Thanks again, and have a great day!