My ‘go to’ product is Ajax or Jiff.

Maybe get some advice/tips from a bathroom company?

I dont know about tiles etc, but I know it’s never come off towels or bed linen. It’s a real bugger

I would first sqeeuze some lemon juice on it and leave that sitting for a while, then take a cloth with pure dish wash liquid and treat the stain. When it doesn’t work, you could always use a bit of bleach.

A good cleaning product and scrubbing has removed unwanted stains from our bathroom.

Magic eraser! It gets rid of everything