My trust certificate is showing a different number than the one I’m supposed to be using

Greetings Orejon210tango,

There are a variety of trusted certificates that install when visiting websites. There isn't a specific way to switch the certificate currently being used. From the description it sounds as though you are following the steps listed below to view the certificates currently trusted on your iPhone. In addition to following these steps to view the certificates as you have, you can learn more about trust and certificates via the following article.

1. "Tap Settings > General > About
2. Scroll to the bottom of the list
3. Tap Certificate Trust Settings"

List of available trusted root certificates in iOS 13, iPadOS 13, macOS 10.15, watchOS 6, and tvOS 13

Take care!