Hi @Pieter22
As @codevenkat mentioned it should be in your default solution. You can also try the below method
If you are sure that you are in the right environment, then try pressing "Ctrl+ F5". It will do the hard refresh and reload the page.
Another way of checking your apps is
1. Go to https://admin.powerplatform.microsoft.com/
2. Select your environment
3. Under Resources > Click "PowerApps". I have attached a screenshot for your reference.

4. You can find all your apps here.
Hope it helps.
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