Your software
My Mautic version is: 4.0.1
My PHP version is: 7.4
My Database type and version is: mariadb 10.4
Your problem
My problem is:
When doing a QuickAdd of a contact of a user email that already exists it notifies that there is already a contact there, however when I click save it creates a new contact with the same email address. So there are two contacts with emails test@test.com