How have you changed your customer support process as you've added team members?

Our earliest set of customers for our HR Tech product have grown accustomed to emailing me directly when they need support. Early on, this was great, because the questions and issues directly fed back into our product updates. They got used to quick, direct issue resolution.

We've added people to the team to work with customers, but unfortunately despite my best efforts, our customers still email me directly for support. I can't get them to email another support email address (i.e. Zendesk) or use our ticketing system in our dashboard.

Have others experienced this issue and how have you gotten past it?