It's been a while since I looked at this but is there a way on their site to submit a feedback request or something? Might be worth trying to submit the explanation of your issue to their website technical support, in case the staff there can pass along the message to someone who can fix it.
Otherwise, if you can't get through on the phone and the above doesn't work (or doesn't exist, who can say with the current admin) it does seem that as long as the DS-160 and passport are correct, the staff at the appointment - at least in the before times - can quickly and easily correct the profile data on the spot without charge.
After all, this must be a very common thing that they see all the time..