Opening forms on an Ipad

I have a number of forms that have been created using Adobe and they are emailed to staff who use ipads, within the last few days the forms for some of the users open as blank pages, they can click on the form and a box appears suggesting that the form is there in the back ground. The only thing I have managed to work out is that the ipads in question are running the latest version of acrobat on the ipad. Can anyone suggest a fix for this or know if I can downgrade to an older version on the ipad?

Thank you in advance for any help.