I also had this try resetting your modem I think this is what I did to fix. Just be patient and it will go away
Rebooting the Ignite gateway will assert the correct MWI state but that should not be necessary.
My main problem was that callers would leave me voicemails but the message waiting indicator status would not change, on any of my phones, to alert me to new voicemails. However, the status would update (on all phones) if I restarted my gateway, logged into onlinevoicemail.rogers.com , or dialed *98 to check my voicemail status.
I informed Rogers of this issue, what worked, what did not, and what (in the back-end integration between their phone switch and voicemail systems) I thought was causing the problem. That information got logged into a ticket, escalated, and the technical teams seemed to have fixed the problem. My Ignite Home Phone service has been working properly for the past several months now.