How to access folders shared to me on Files app, iOS?

Recently a friend and I were trying to set up a shared folder on iCloud Drive, but when he sent me the link to access the shared folder he created, and I tapped the link (I was on my iPad), it sent me to the iCloud website. There I could view the shared folder, but when I tried to access the files of the folder in the Files app, the shared Folder didn't appear on my iCloud.

I am very confused because before this, I could see and use other shared folders inside the Files iOS app, but this time, I just can't open the shared folder neither on the Files, or Pages, or Keynote iOS apps on my iPad, and only I can view the folder on the iCloud website