I had a similarly awful person in my life who committed crimes against me that sounded completely absurd and people (including the police) thought I was crazy. It was difficult to find evidence because video surveillance is not allowed on private property in my country.
I asked Belial, Paimon, and the Angels Elubatel and Ebuhuel for help many times. They managed to stop him for several months and helped to convict him with witnesses. (But it took a long time).
I never perform elaborate rituals – I just call upon the spirit. When I contact someone for the first time, I use this seal:
I’m keeping my fingers crossed for you!!
Did you report the bloke to the police?