Person keep saying my number is his!

Hi all, there is this person that is calling me multiple times and saying that my number is his and saying he will complain. I have been using this number for years and out comes someone from the box. I tried calling him but he doesn't pick up. Just giving missed calls and not stopping. I have blocked him. But when I check the block status, he continuously keeps calling. And it all goes to the blocked zone. Attaching the number and name of the this person. I have raised a cybercrime complaint against this person. Advise.