> I believe this has arisen because of an incident on 31st of May 2021 when I was walking in a park in Cambridge where I live and someone in a car tooted their horn at me twice. I believe the person in the car was my sister visiting my younger sister who lives in Cambridge and it looks as if she thought that I was ignoring her.
Sounds highly unlikely.
If the times match, maybe something was discussed between your two sisters that has resulted in you being cut off. Have you tried asking your younger sister if she knows anything?