Tapping/Rearrange bug on iOS app

I have a problem on my iPhone for the “Tapping/Rearrange” questions: Those where you have to pick a series of words among a list (see pictures).

The first 3 or 4 words labels disappear (see blank space outlined in red in the picture)- so there’s no way to answer the question correctly as the answer words are not there.

I tried to restart the phone, no success. I tried to remove and re-download the courses, didn’t change anything. I tried to reinstall the app several times. At one point it worked, but then the problem came back a couple of weeks later.

The problem is for that type of questions only. It happens on all those questions in every deck.

Most of my courses use that type of questions, so I can’t use my iOS app anymore.