Destiny 2, like all live titles, is prone to occasional problems, issues and error codes. This is especially common with new drops of content, the start of new seasons or the release of new DLCs.
Honey is one such mistake, but it only appears under very special circumstances. According to the Bungie help page, you may have encountered this error code if Bungie manually overwritten public access to the Activity. This can happen if a problem was found or the activity was taken offline before the offline update. Please follow @BungieHelp on Twitter for updates. “
So the short version is that this error occurs when you try to load into a shared public space in the game (Tower, HELM, etc.), but the server you are trying to connect to is not online.