From https://ticket.wikimedia.org/otrs/index.pl?Action=AgentTicketZoom;TicketID=12056073:
In the “Saved” section in the app, some articles appear twice or more times in a list they don’t belong to. I can't see a specific trend with this issue, it seems to happen randomly although the articles affected do change sometimes. If I try to remove the article the duplicate version (which can not be accessed via clicking) still remain. Other than that I don't see any trend with this issue. I am using an iPhone 12 on iOS 15.2 and the app is up to date if it helps to know this.
Seems related to T281614, but different.