Hi @Robert94
1. Go to https://make.powerapps.com/
2. Choose the right environment
3. Select Tables > your custom Table > Forms
4. Edit the form in designer mode
5. Select the field >on your right you can see > hide > select the checkbox and publish it
6. Hit save and publish

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In Design studio
1. Pres sync configuration and preview the website. And press "Ctrl+F5"
Hope it helps.
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