They can only ban it when they detect that you're using it. It's a cat and mouse game.

I still don’t get it. So they detected the usage and banned the app, what happened that made the ban disappear?

Are you saying the app is using a different scraper? This I would get. But earlier comment[1] mentions ban revocation - this is what surprises me.

[1]: https://news.ycombinator.com/item?id=43530821