You are replying to a person who is a member of a group that is here to disrupt.

The unusual brakets {curly brakets} that they use are a signature, so that memebers of the group recognize each other.

Curly Brackets

Unless you are a physicist or a highly skilled mathematician, you are unlikely to encounter curly brackets in your research or reading. If you're a programmer, you would most assuredly use these bygone little squiggly marks. But much like Hypercolor shirts or wearing spandex shorts for anything other than biking, curly brackets have largely fallen out of fashion. But just in case you do encounter curly brackets outside of the above-mentioned fields, they are likely indicating a series of equal choices.

The only other place you may encounter curly brackets is on forums or when instant messaging. In this context, they are used to indicate a hug.

https://www.scribendi.com/advice/square_brackets_curly_brackets_angle_brackets.en.html