It's known, recently, as the "pig butchering" scam, and this is the telltale opener. The idea is that you respond with "hey, you've got the wrong number" and they can then open a dialog of "oh, sorry about that" and then spend weeks or months just conversing with you casually to build a "heh, what a crazy way to meet a new friend" sorta relationship. Eventually, they spring some kinda ask for money or malware on you, because they earned your trust.
Give it a google, it's pretty fucked up, and completely counter-intuitive how effective and profitable it is.