Dark clothes ran into light top in the wash

[limescale]

I have a cream top - 46% polyester, 43% viscose, 11% elastane.

Something dark has run in the wash (I presume) and stained it. Either that, or something in my airing cupboard leached onto it when I hung it there to dry.
Pic attached (once approved).
I didn't notice it at first (it actually looks worse in the image than in real life).
I've washed it again at 40C and there's no change.
It's not like a normal stain that you can treat, more that it's been dyed.

Can anyone suggest anything to remove it?

I would wash it again with a Dylon stain catcher sheet. Sainsbury’s sell them

The same as pp said, colour catchers are great but you need to be quick.

Thanks. I have not been quick. At all.
Washed it on Monday, packed it to take away for a couple of days. Noticed it when I came to wear it. Only washed it today on my return.
I will try the colour/stain catcher - it can't do any harm.

Yes worth a try