I have this same setup and this conversation happens often, you get used to it happening and navigating it.
ON only one occasion in ~20 years, someone refused to do business with me because they thought I was impersonating them and told me I was being disrespectful by using their brand as my email, and even after explaining how it works they weren't happy.
ON only one occasion in ~20 years, someone refused to do business with me because they thought I was impersonating them and told me I was being disrespectful by using their brand as my email, and even after explaining how it works they weren't happy.