Strange Effect of Spam Text

I have a relative I’m trying to help remotely because of Covid. They received a spam text message pretending to be from Vodafone (+44 7901 060088). This has caused a profile icon to appear at the top of the main Messages screen, with the number that sent the text, above the listing of the other messages (sorry about poor quality picture rather than screenshot);

The text message itself is not listed in the messages, but if you click this profile icon, it brings up the message;

There doesn’t seem to be any way to remove the profile icon from the message app, or to delete this message (as far as I can tell remotely).

Does anyone have any idea what has happened, or how to fix it? I suggested a full reset but they are nervous about doing that...