Faulty washing machine ruining my clothing

I purchased a series 4 washing machine in November 2023. Within 4 months, the machine started leaving brown stains on my clothes. Sent in twice under warranty. First time I was told there was nothing wrong. I redid my entire scullery plumbing - and the marks still continued. 2nd time was told it was a grime build up I do drum cleans twice weekly, use hardly any soap (only ever Omo) and even less Stasoft. The stains are back. The stains do don't wash out, not even in bleach. 3rd time now the machine has gone in, under "warranty". Drum was replaced, all seals are clean. Now I sit with zero feedback, waiting for "Unilever" to respond? No accountability. I am so blessed to have a machine, yet I can't even use it? Countless clothes ruined, to the extent that I have to throw them away. Can