Excel on iPhone/ default app

Hello, untill yesterday I was able to open .xlsx files in Microsoft Excel just by tapping the file in Files app, but for some strange reason that isn't the case anymore. Now I have to first open the Excel app, and from it open the .xlsx file, and if I try to access the .xlsx file directly from the Files app, it will just open a preview that i cannot edit. And when i try the get info on the file, there isn't an option to open by default with another app. Any help?