Btw did you update the SDK?
Under window > Toggle System console. This will show a black window with command prompts
Back to blender
Go to preferences > add-ons > armory > update SDK.
In the system console you can see data being downloaded. It’s done if nothing happens after a few seconds. Clean your project and restart blender.
If you get an error make sure you install git first. It’s the option next to update sdk