Thanks for reaching out. We're sorry to hear that Lightroom Mobile is not working for you.
Which version of the application are you using? Can you tell us what error message you see as the screenshot shared is in a different language which I don't understand? Can you share your registered AdobeID with us?
What is your device specification? Did you try and re-installed the application?
Are you able to sign in?
We're here to help, just need some more info.