Hi there @Laura7135 👋
This is really interesting and I wondered if you'd be able to provide us with a screenshot of the message so we can see when it was sent (there's usually a date/time stamp on them). It could be that it was a notification from 2020 and not a new message but a screenshot would help us clarify.
If it is indeed a bug, I can then take this away and raise with our tech team.
Looking forward to hearing from you,
Rebecca 🌟