question

I recceive an excel (.xls) attachment in a message in the Gmail mail client on my Android phone. I used to be able to click on it and it would open in Drive. This is the behavior that I want. Why does ringcentral app download this into documents? The ringcentral app never asked my permission to behave this way. How to stop this behavior? Why would this be the default behavior? This makes me extremely angry because then the ringcentral app tells me that I have no apps capable of opening xls when this is not true. Please don't remove functionality from my phone.