If you keep your wits about you, yeah, you got a winnable case for at least a portion of your money back, and if you go for -that- portion only, then you might get lucky for 'punitive damages' as well. But it hinges on your ability to appear 150 percent the most ideal perfection of the Great God "Reasonable", calm, cool, collected, considerate, compassionate, coherent, cooperative, and just a small tiny bitty pinch of confrontational salt called "righteously indignant" but avoiding the Nancy Grace vulgar peasant extremes of theatrical drama, "The courtroom is a place to act like adults, it is not a school yard."
The technical argument is simple Law of Mathematics; You gave 550 for 12 quarts of milk to be delivered, but they only delivered 2 half pints, so there's still 11 -quarts- of milk that you paid for and never received. Or a bucket of hot wings but only the little containers of dipping sauce were delivered, empty. Or a Carpet Shampooer, but they only sent the power cord. Or any other examples you can think of where you pay for "a whole" and the most important portion never got delivered; You understand and appreciate that "a workman is worthy their hire", so you you don't care about the Delivery person's wage, and even the tip is excusable - But the Owner and Underwriters of the Shop itself still owe for the goods they got paid for but failed to supply, provide and deliver.
oh. and if some variant of the tired old saw peeps in about "that wasn't my understanding", that's fine, contract law number one demands "meeting of the minds", "mis-understanding" -annuls- a contract "ab ovum" -before- "consideration" is acceptable. So in the case of "misunderstanding" or "not what -I- heard", or "don't recall mention" and so on, the 550 -never- should have been accepted in the first place since "no meeting of the minds" ever existed.