Was your sales guy a total moron?

About 2 months ago my dealer cold called me to upgrade from '24 lease to a '25 lease, I did the credit app to trade in my current lease for a new lease, he offered me a monthly payment less than half of what I am currently paying...seemed too good to be true. I finally had time in my schedule the 1st week of Feb, I cleared out my truck, scheduled to trade in on a Tuesday, he called me that Monday and said he made a massive calculation mistake and the offer is no good.

Is this bait and switch or him being a moron? How do you screw up something like this?