opening PDF in diverse apps without default PDF app

I have PDF files in my Android, especially in Dropbox. When I open a file, it's opened by the the Dropbox PDF Viewer. Once opened, there is an option, the button"Open with". If I open the the button, a little window opens with a choice of PDF apps, as Adobe Acrobat, CamScanner, Xiaomi PDF Viewer, etc. When I choose and app, I can click on 'just once' or 'remember this choice'. I'm not sure that I reproduced the accurate words. I'm accustomed to click 'just once'. But accidentally I clicked on Adobe Acrobat, remember this choice. So the PDFs went opened everytime with it. I want to reverse the process and get back the multiple choice. I tried to find a way through the app settings, but nowhere I'd find Adobe Acrobat as default settled. Can someone guide me how to get my old setting? Note. My phone is a Xiaomi Poco F3. Note: I tried this: 1. Apps 1. Manage Apps 1. (A vertical line of three points in the right upper corner of the screen) 1. Other settings 2. Default Apps 3. Opening links 4. To deactivate Adobe Acrobat reader. But it's inefficient. Can someone give me a solution?