Looking up the phone a little, I'm guessing it's a problem with SSL support. Does it give you any error messages other than the server cannot be found? Does it prompt you for using SSL and setting the port number?
You may want to try calling Verizon tech support. They can tell you things that we don't know. You can point them to the configuration information at https://uknow.drew.edu/confluence/di...ent-IMAPAccess
and ask them if that's all is needed, or if the phone can be configured with those settings.