Neighbor’s Window Is Melting My Siding, What Do I Do?

Located in NJ, here’s the situation.

My mother got brand new siding and a new roof last year, and all was well until a few months in when we noticed the siding was misshapen. After a few weeks, we noticed it was the glare coming off the neighbors window that was melting it.

We attempted to talk to the neighbors, who used this home as a vacation property, who flat out ignored us. Now, the home is under a realtor, and they’re also ignoring us.

Who do we contact to get this issue fixed? The siding company refuses to replace the siding, claiming the damage isn’t covered. Do I contact the city?

I have photos of the damage, if anybody wants to see DM me pls.