In how many places are user emails stored?

I changed my account email. But that didn’t change my community email. This is rediculous. Crazy thing - I log in with my new email, but notifications come to my old email. So I ask Deezer staff to change my community email (another absurd thing - users cannot do it themselves!). Staff changes my community email. So I notification come to my new email too.

Now I suddenly receive a notification to my old email again! So, after TWO changes my old email is still in the system. At how many entries in database are emails strored? Why changing an email once do not change it? What should I do to remove my old email from your system completely?