Notice of Cancellation of Service Contract

Notice is hereby given that we cancel our contract dated _____, 20 _, for _________________________ [description of Service] to [name of firm], for the following reasons:
That on [date], you breached said contract in the following respect:
Cancellation of said contract is effected on [date], and for any subsequent service contracted for in said contract, inasmuch as your breach impairs the contract as a whole.
[We claim damages from you in the amount of $ _____.