User has to click on "open this page with Appsheet" after clicking Icon

[dev2]

Hi all

One of my users (only one) has a pop-up asking “open with Appsheet ?”, but this did not use to happen.
This happens only when he cliks on an app launcher icon on his device.
This pop-up appeared 3 weeks ago.

I suggested him to delete cache and reinstall the app launcher, he says that does not change anything.

He’s using Iphone.
Here is picture of what he gets :

Any clue of what I could say him ?

Many thanks for your help !