Hi!

So recently, I went on GB Studio to comment, but I can't. I told my friends if they had the same problem but they said that they could comment! But I couldn't! So can someone tell me how I find out if I am banned from posting an itch.io topic or comment without creating a secondary account?

I don’t think there is a way to confirm if you are banned from commenting, apart from the method you mentioned.

without creating a secondary account?

I can’t remember of the top of my head if this is against the rules or not, but keep in mind if someone is banned from posting on a specific project page, they are banned for a reason. Just because it’s possible to make a new account, doesn’t mean that’s the way to go.