Good Morning,

hope you are doing good, as you mentioned you forgot the registration number of eamcet, don't worry!! From EAMCET official website under login/signup page you will get an option of Forgot registration number by click on it you will redirected to new page, you have to fill all the details and then they will show you your registration number.

Hope this is helpful if you have any other query you can comment it below.

All the best!