Blank card on returning to the app

I have been having a problem with the iPhone app over the past month or two. Sometimes a card appears blank, but only when I return to the app after a while. When I switch back to the Anki app, the card I was in the middle of reviewing has become blank. I can tap edit, which works, then the card is visible again after I cancel out of edit mode.

Any help is much appreciated, thank you!

This is caused by iOS; automatically reloading the page when it happens is on the todo list to look into.

Oh ok thank you