Long story short. Today I was having some trouble with one of my email addresses. I raised a support request with the hosting provider. Within a few minutes, their technical support person replied back telling me that nothing is wrong at their end. And then, soon after, the problem was gone, which was a bit bizarre. So I logged into the website control panel, and found that the last login time was just a few minutes ago, and traced the last login IP address to the hosting providers network IP address range.
If you wish to retain a customer and provide better service, then don’t act shady, take responsibility for your acts, and apologize to your customers when it’s due.