My wife’s Thunderbird has had problems for several weeks. To repair them, I have disconnected from our e-mail provider (Proton.me), & reconnected to it. Everything seems to be fine but her Thunderbird Inbox. There are no emails in it, but it insists there are two (2). I have tried to compact the folder & to repair the folder, but these actions have no effect. How do I get her inbox clear of this problem, so I can focus on her bigger problem?