iPhone 15 Pro Max poor cellular service and network connectivity, lots of drops.

Our new iPhone 15 Pro Max's have poor cellular service and frequently drops cellular/network connections. Both me and my wife have the iPhone 15 Pro Max and we both have the exact same problems. It has become frustrating and they are basically unreliable and unusable.

At first I thought it was the carrier. So to confirm or rule out if it was a carrier issue I swapped sims with my old iPhone 8 Plus that has a different carrier than our new iPhone 15's. I literally did a switch between the two. The result, the iPhone 8 Plus did not have any cellular/network connectivity issues with either carrier, and the iPhone 15's (both) had connectivity issues with both carriers.

Something is wrong with the iPhone 15. The odds that both of our new phones have the exact same problem is not some random fluke.