On the User Sign In Screen, click on the 'Forgot Sign In button'. Further click on the To Recover User Sign In ID 'Click here' button. Then select your user category and enter the E-Mail address and click on the Submit button. All Sign In IDs linked to your e-mail address will then be compiled and sent to your E-Mail address.
Road Map - To Recover Sign-In ID.
User Sign In -> Forgot Sign In button -> To Recover User Sign In ID 'Click here' button -> Submit button.
( 'User Sign In' is the screen were you enter User Sign In ID to Sign In to our application.)