Okay, so here’s where you need to turn into an armchair lowyer. I learned this trick at work when dealing with people who have the memory of a goldfish. You need to get everything in writing, not just your interpretation of what you think they want, but their confirmation of what they want/require.
You get their “guarantee” and the steps you need to take, and painfully recite back each and every step along the way, asking yes/no is that correct.
Describe the problem, cite the “guarantee”, ask for an RMA. Ask for where to ship it. Ask for what carrier(s) they prefer or even require. Become a broken record and re-ask everything until you get a clear concise answer. Recite back, get confirmation.
Then follow the steps To The Letter. If they say USPS is okay (and that they’ll reimburse return-shipping costs), and later they claim that they don’t have a tracking number from USPS or some other way to weasel their way out, you can go to Chase/PP/whatever and cite back the exact email, the receipt from USPS, etc., that you followed their instructions to the letter.
In short, you need to prove yourself right. Imagine you’re going to court, and Judge Judy is just itching for any excuse to call you an idiot and rule against you. You can’t give her the chance.
“We didn’t receive your light, as it wasn’t tracked.”
Well Hell’s Bells, I asked specifically if XYZ Shipping would be okay, and you said yes.
And so on.
That’s why even though it’s a pain in the ass, I often video the Grand Opening of the package, just in case anything’s missing. You order 3 doodads, and only get 2. “No, we ship 3. We have packing list, say 3. You try cheat us!” That’s when you send the video showing only 2 doodads were inside. Otherwise you say they didn’t, they say they did, you lose.