In the HBR article, while highlighting some live examples on how people publicly complained inappropriately, they also give some decent tips to be aware of if we ever need to make a complaint:
Frame your argument. At first, don’t attack, explain. There may have been an honest mistake or misunderstanding. Don’t put the seller’s representative on the defensive prematurely.
Propose a resolution. It helps the seller resolve your problem if they understand what they might do to satisfy you. For example, do you want a defective product fixed or do you want your money back?
Show respect. Chances are the seller is honestly trying to help you. Convey trust in the seller and you’re more likely get a quick resolution and build an enduring relationship.
Keep your cool. If you don’t, a seller’s representative may reasonably decide to hang up on you, or at least will be less inclined to help you.
Escalate if necessary. There is only so much that most salespeople are authorized to do. If a seller’s front-line representative cannot give you satisfaction, go over the representative’s head.