If your client has granted you service provider access to their cosmetri account, they will have added you as a user. This requires that they enter the admin username of your Service Provider account, ensuring that the account is then linked to you. You will be notified by email at the email address registered to your Service Provider account. This email will include an activation link that you need to click on to set your password. You can then login directly to their account under ‘My Clients’ in your Service Provide account, or by using the standard login page and entering the username and password:

https://www.cosmetri.com/admin/login.php