Our main number (tollfree) shows as 'Voice and Fax' and there is no option to make it voice only. About 90% of our missed calls are failed faxes to our tollfree number. This is a common form of spam from fly-by-night travel agencies and the like. How do I set it to voice only? I have no intention to "Act today for a one-time package offer to Mazatlan" or get special pricing on federal labor law posters or lower my credit card processing rates.