We sell a mix of products, some paid, some free. Our brands for these products are completely separate, and on the websites for the free product we don't give out our phone number (and direct people elsewhere to get help).
However, occasionally people still figure out our phone number.
While I love our customers and I definitely want to hear from them, we just don't have the resources to respond to phone calls for our free product (there is no paid version of this free product). I'm just not sure how to convey this to them at the moment they have a problem.
Also, we always answer the phone when people call, so there's no complicated phone tree to deal with.