Mispromise

witness testified that no trickery, deceit, coercion, or fraud or mispromise had been made to him to induce representation by public officials.

Source: wiktionary

Back then, any time he spent on one project he stole from another. That was the cause of what he calls his "one flagrant mispromise."

Source: wiktionary

In most industries with concrete tangible products, this kind of overpromise is rarely seen, but with intangible brands very serious overpromises or mispromises can be made where the brand promise collides with the reality of the actual service.

Source: wiktionary

In your language be simple and clear as you can, Let no sort of deception e'er enter your plan; Never threaten with objects terrific and vain, Nor mislead or mispromise compliance to gain.

Source: wiktionary