It seems that there is problem with the implicit transactions.
I have ran the example from here https://docs.phalcon.io/en/latest/reference/models.html#implicit-transactions using https://github.com/calinrada/PhalconUserPlugin/blob/master/Models/User/UserProfile.php and https://github.com/calinrada/PhalconUserPlugin/blob/master/Models/User/User.php. The profile record is saved, but the user_id field is null.
Any ideas ? Thanks.