Why I can't update the Apple Store App on my iPad Pro?

The Apple App Store app itself will only update when you update your iPad it doesn't update by itself. If there are apps individually that you want to update, you can open the App Store, and up in the corner, you'll see an icon of your Apple ID. You can click on that and get options that allow you to update apps that you have downloaded, allows you to see apps that you have downloaded or purchased before or on other devices.

Open the App Store and scroll down to the bottom. Tap Account. Tap Updates. Tap Update next to an app to update only that app, or tap Update All.

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