For a year now, I have been using the fax console to send and receive faxes, from people across Canada. Since last week 2 of these people could not send me a fax. My console answers the line, I can hear the fax noise, but then the line ends. These people have faxed me successfully in the past and others are still able to fax me now. Any idea why only a few people cannot get through now? How can I fix this?