Well you've obviously got into AB somehow!
(A different device, perhaps?)
There's no reason why any particular operating system should dislike your password. (It's not your OS that handles it anyway; it's your browser). The usual reasons for password problems here are
(a) clicking 'Register', instead of 'Log in', by mistake ; and
(b) having the Caps Lock on (or otherwise not using the correct case).
There's no special app for accessing AB, whether for Windows, Android or any other operating system. You have to go via your web browser (which should be Edge on a Windows 10 machine unless you've had the good sense to install a better third-party browser, such as Firefox, Chrome or Avant).