A bit more description of what you mean by "not working" and the PS version and OS would help.
I press on the icon Ps and it open window with Sign in Required I press Sign in now and its hover on downloading . its not signing in and I can't open it I restart my Mac and it does same thing
You still haven't indicated the Photoshop version or OS.
In the meantime try resetting your Photoshop preferences:
Close and relaunch Phostoshop, and IMMEDIATELY hold down Ctrl + Alt + Shift (Windows) or Cmd + Ctrl + Opt + Shift (Mac), and respond in the affirmative to the dialog asking if you really want to replace the preferences. you must be extremely fast on the keyboard (if you don’t see the confirmation prompt, you were too slow)
You may have to do it a couple of times before you get the hang of it!