Well this was interesting. I had a guest that after their stay and having to contact CS at Airbnb it was decided that I really needed to block them. This came from CS. I followed what looked like the logical honest steps to Report and subsequently block this guest. Nope! Wrong! It isn’t as simple as that. However, with some help from a manager, the secret was revealed. For those of you that wish to know, here are the steps and screen shots are attached as well.
Go to your conversation with the guest, under their profile picture hit Report, then when the What’s Happening? screen comes up, hit I think they’re spamming or scamming me. The next Screen will say What’s Happening? again then you hit They advertised or solicited something. The next screen will read What did they advertise or solicit? Hit the appropriate button (in my case House Rules) and hit Submit. On the We got your report screen hit Block this person and OK Tada, done!! I hope this helps for the future.