Nespresso XL frother not fit for purpose — refund refused

I bought a Nespresso XL milk frother that doesn’t work as it should. Using the same milk and setup that work perfectly with my Russell Hobbs and Severin frothers, this one makes soap-like bubbles that collapse in seconds and leaves half the milk flat. I returned it within seven days, followed all instructions, and Nespresso’s “technical centre” claimed there was no fault. If that’s considered normal, the product is not fit for purpose. I’ve requested a refund, not a replacement. The product is sub-par and service from a supposedly premium brand has been slow, dismissive, and evasive. I’d appreciate a proper response here from Nespresso management.