I came on to say the same as @HopeFloatsAbove .
If you don't have to ever see them again then block them.
If, like me you have to co parent with them (it's been 14 years now and he's got worse every year) then Grey Rock is your friend. I get blamed for something virtually every day. But I ignore all the shit and accusations and reply back if required and only short factual answers.
But unless you absolutely must have this person in your life - don't ever engage with them again. They love it, and love seeing you react to it. They live for it. Don't give them that satisfaction.