Were it me I'd look around for someone in the legal profession and get them to write a legal-sounding letter (on letter-headed paper) along the lines that they have failed to provide what was ordered and their persistent attempt to extort money from you is whatever the offence is termed locally, stalking? Harassment? and you'll take legal action if it doesn't stop.

Another way would be to discredit this person under a pseudonym (of course) on Twitter and whatever social media you can get to without revealing who you are.

The only spiritual way I can think of is magic in one degree or another. A banishment might work.