This is how Meta works: the profile followers audience has no time window. It always includes all current followers. That's why it's created as a single audience named in the pattern IG - [FOLLOWERS] - Everyone, no matter how many periods you selected. The same goes for the Facebook audience of people who like or follow the Page, which is also created only once, as FB - [LIKES] - Everyone. In the page counter, these two count as 1 audience each, while the other types are multiplied by the number of selected periods.