Yes, in this case it was a typo. I think. But as wheresTheHoney says, it's confusing because sometimes (occasionally) curtains are sold individually.
I did get a pair!!! but not before I'd panicked and ordered again. I should have waited. I have to return the other pair now. I hope they fix that. Maybe I should have rung to check, not sure you can ring, it was a bit confusing.