Modifying an order IMPOSSIBLE (then refuse discount)

I ordered a $3000 Alienware using a SAVE12 coupon. Wanted to UPGRADE (give them more $) before it was shipped) I was told this is impossible I must cancel and reorder. So I said fine no problem but I want to apply the same coupon code. I am told "it expired. sorry . nothing we can do" Seriously? So I cancelled and have been trying for nearly a week to get someone to just give me the SAVE12 coupon I ordered on the first purchase and all I get is "I will xfer you to the change team" then the change team says "i will xfer you to the sales team" and I am stuck in a transfer loop. So then I see I can sign up for dell emails and get a 10% coupon. So I sign up and never receive the coupon. Then I have my dad get the military discount code. I apply the code and it says "this coupon has already been used and is no longer valid" I never used it before. This whole company's customer service is beyond terrible. It almost seems like they wont lift a finger even on a huge purchase. They dont want to make money I guess? Complete nightmare from start to finish. They must be losing out on millions of dollars because all the other posts reflect inept customer service. I have complained on social media too and gotten no response. You need to move you call center to America and get ppl who care about doing things the right way. I have been hung up on multiple times, send numerous emails, tried chat support. There is absolutely no one who has tried to help me. I honestly barely even want the computer anymore. I don't feel like having a company that doesnt care about their customers make money off of me unless they really show me they care.