Strange stain on shirt that looks dyed?

[hancw522]

Hello!

I did washing the other day and just noticed on the drying rack that a shirt appears to have strange red blotches on it. It's quite odd because I don't think bleach could have done it (not sure where bleach would have come from anyway) because the shirt itself is a maroon colour and the blotches are a more vibrant red colour - surely bleach would remove the colour?. I've linked images of the shirt

None of the other clothes in the wash appear to be affected. It was a normal wash cycle on 30 with a non-bio pod (ones I always use that I've never had any trouble with in the past) Was just wondering if anyone might be able to shed some light on what happened to this shirt?

ibb.co/YQxL8ZD
ibb.co/FW7FqNz

Over the last year I’ve been getting dark rust coloured marks on whites. I’ve not noticed them on anything darker though. They absolutely won’t wash out no matter what stain removers I’ve used. I don’t know if they’re from my washing machine, stain from the chest of drawers they’re in or what. About 2 years ago I replaced all my bedding and towels for white ones and they are nearly all marked now. I hope someone knows what might be causing it.

Forgot to attach pics