App doesn't work on my Ipad pro

Dear all,

I'm using Adobe Digital Edition on my IPad Pro.

it worked perfectly until yesterday.

But yesterday I bought new digital book and I tryed to install it on my ipad.

now, when I open the app, I only see a blank screen.

I try all buttons bug the app is not reacting to any of them.

can you advise me on the steps I should follow to solve that issue?

Thanks!

Jaehoon