ODM Updating with save cause duplicate entries

Hello guys!

I'm fighting with a problem for a considerable time, and I can't find a nice way to fix my issue.

Let's say I have two tables:

uses (id, name)

uses_phone (id, user_id, phone)

Supposing I have created a users (1, 'Mary') and her phones users_phones (1, 1, '123') (2, 1, '333')

If I want to update Mary, to change her name to "Maria":

The save() method will NOT delete the actual records in users_phone, but will insert new entries, and then I will have:

1, 1, 123
2, 1, 333
3, 1, 123
4, 1, 333

Which is the best way to solve this issue? I'm a bit confused. I like using Model instead PHQL (I like it too, but Models with ODM seems quie magic).

Thanks for reading and please forgive my bad English.