Worst after sale service from HP

As an executive of an International organization, I bought a top of the range Elitebook from HP. The laptop had a sound problem and the speaker was replaced onsite. Unfortunately this did not solve the problem. After a 3 days it was decided to replace the motherboard. The wrong part was ordered more than two times and every time I was promised, next day it will be solved. After speaking twice to supervisors from HP helpdesk, at last After 2 weeks the motherboard was replaced. The sound problem was now solved, but the screen now is covered with black spots. The engineer said he was aware of this,but anupdate will solve this. Nothing was solved and after another who knows how many phone calls, I requested a replacement because the new laptop was now twice opened and still faulty. This request was filed and a answer would be given within 24 to 72 hours. Needless to say I had to call again to get the answer. My request was rejected and I was told some more fault find will be done. Almost 3 weeks without a laptop and still no end in site. I complained and was promised that public relations will give me a call on Friday afternoon. Needless to say, no phone call. Absolutely disgusted by the utmost disrespect from HP. 3 Weeks of how many phone calls, disappointment and worst After sale service ever from a company. Next option is to raise my terrible experience on social media, because HP not bothered the sort out their own mess. Sustained Excellence they say. Shame on you,because my only request is to have a workable laptop that I paid for.