Why can't I edit photos with Acrobat Standard on PC but I can with Acrobat Premium on my iPhone

I think the title says it all.

I have the text recognition on photos with my iPhone, but it doesn't work for the same photo exported on my computer.

( I see that once i'm in "modify", if i click the little wheel for "parameters", the option "recognize scanned text" is greyed out 😞 

Can anyone help ?

Thanks !