Error 1801: security error

so I was using the MIT app inventor app on my MacBook 2020 M1.
I kept receiving something called 'error 1801 security error receiving blocks'.
What does this mean, and how do I fix it?
calculator_2_1.aia (16.9 KB)

Every call App Inventor makes to the companion app is signed using a hashing function (specifically HMAC) and the companion verifies that hash before executing the code to protect against rogue apps that might try to make your phone execute malicious code. Error 1801 appears when the companion attempts to verify the hash but fails, so it refuses to execute your code. I was able to repeat the error using your project so we'll look into what's going on.

So it looks like there are two things going wrong here. The first is that because your app enables HighContrast mode, but this isn't an option yet on iOS, it throws an error during initialization. Somehow, this gets interpreted as a security error but we still need to track down why. After I turned off the HighContrast property on Screen1 I was able to get the app to load.

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