Meural Canvas II - repeatedly shows “WiFi Restarting…” message

I have two Meural Canvas II displays on my wall and both of them are repeatedly showing the message “Restarting WiFi…” every few minutes. The Meural app and website say that they are “online” but the last sync date is one month old. I have an original Canvas (pre Netgear) and it’s working fine at the same location on the same WiFi network. 

Firmware version is 2.3.2_2.0.12. I have removed and reconfigured the Canvas II models several times but that doesn’t help.