Please try the following methods:
1. Try logging in from other devices.
2. Log onto your Facebook before registering with COSMERIA
One possible reason why you cannot log into COSMERIA is because your FB account is too private to create social login.
- Check on your "Apps" under "Setting". If you have managed to log in, you should see "Cosmeria" in your app list.
- If you don't see this icon, that means your account does not providing all facebook personal information for cosmeria to create account. Please note that Cosmeria requires name, email and post access to create account for users.