Difference between local and example build on gatsby cloud

I am new to Gatsby and I am trying to use Gatsby + Sanity as a headless CMS. I have gotten things running ok and I can modify the data in sanity and see it show both on my local after a yarn start and on the demo link after a build in Gatsby cloud.

The problem arises in that there are differences between what shows in the cloud and my local. Most things work and show the same, but three of my nav links do not work. These show just fine on my local, which is using the same sanity dataset. I know that they are connected to the same place as well because I can change some text in sanity, and it will show in both places. I cant figure out why there would be differences, but only for some things.

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