<img width="1127" alt="Screen Shot 2021-05-22 at 7 19 40 pm" src="https://user-images.githubusercontent.com/77184153/119221414-aa9b5e80-bb32-11eb-9a44-55fdc32ef38f.png"> It says the error is coming from the line: const existing = this.groups.get(group.id);
It says the error is coming from the line: const existing = this.groups.get(group.id);