Minecraft Realms buy/trial dialog won't close

A friend and I are both experiencing a bug: we've been part of the same Realm for a few days now with no issues, and we've checked with the host who has confirmed they haven't uninvited us or anything like that. However, the system seems to be behaving as if we aren't part of any Realms: the dialog prompting you to buy a Realm or get a free trial is open with no way to close it.