Need help: found json error while bug hunting

Hi all, apologies for the silly question if it is, but i was browsing a website for bug and then i found one link which show some json diagnostic error:

i have uploaded a screenshot of error.
link:

please help me out if somebody knows something about this.

Dear bgxdoc,

have you added any kind of special character?
if it is because of that char you might need to follow the source code to find for the root cause of this, it might lead to XSS or others bugs.

but if it is a developer’s mistake then nothing can be done.

Thanks!

I apologize for replying this late. I was out of town. And thanks for your reply. It was helpful. I found out that it was a developer’s mistake and as you said nothing can be done.