Check in your own mail program, with which e-mail address you are registered with Coret Genealogy (search for mail with sender firstname.lastname@example.org).
Enter this e-mail address on the 'Forgot your password' page (available in the top right menu) and follow the instructions.
If you do not receive an e-mail as described in the previous point, it may be that 1) the e-mail message is blocked by a spam filter on your side (your e-mail program or your internet provider) or 2) that the e-mail address is not known at Coret Genealogie. In this case it is best to register again. You will find this option in the menu at the top right.