Received a call from this number with no message left; called back to an automated answering machine for Optima Communications International, a marketing company. Only option to leave name and number to receive a call back. Checked their website and phoned their head office phone number, which is different. Spoke to operator there and had my number removed from their data base for all their clients.
Called the number back and it's Optima Communications. I called the Toronto head office (416-581-1236) and spoke to reception. You just have to ask them to remove your number. It takes 30 days to take effect though. Receptionist was very friendly and apologetic.