I killed my sourdough

I think I killed my sourdough.

I'd been having trouble with mould appearing on the surface and it seemed like I was regularly having to scrape off the mould and grow the starter up from a salvaged tablespoonful.

I added a slug of 10% acetic acid vinegar thinking that would keep the mould at bay. And the lactic bacteria like it acidic, don't they?

It also kept the yeast at bay. Dough made from this starter is now showing no signs of growth. I am quite upset.