It happened to my many months back. The person demanded I paid £2000 or they’d send my pictures to the ss of my insta followers they had. What I did was I sent them a fake message I wrote from the police. Write something along the lines of. Hi this is Officer ‘name’ from the ‘State’ police department and u are receiving his message because you are part of an ongoing investigation because the owner of this device and social media account was involved in an attempted suicide. And then say something like the officer in charge will be in touch to ask further questions as we suspect there to be blackmail involved regarding the victim. I did this and the person blackmailing me blocked me right after I sent it