I just received a C&D letter from my former employer asking me to stop contacting their customers and having them switch over to my new company. The problem is that I'm not contacting them, they are contacting me because the old company's office personnel aren't answering the phones. The customers reach out to me after failed attempts with the office and that's when I notify them that I am no longer with that company but that I am with a different company. That's usually when they ask if they can switch to my new company and I tell them that it's up to them. Also, I do not have a non compete from the old company nor did I sign anything stating that I wasn't allowed to communicate with former customers. Should I be worried?