That might be the issue, try changing it to https://api.twitch.tv/kraken/oauth2/authorize
Also, just to check, are you a game developers? because the scope you’re requesting is for using Drops, which is for games developers.
That might be the issue, try changing it to https://api.twitch.tv/kraken/oauth2/authorize
Also, just to check, are you a game developers? because the scope you’re requesting is for using Drops, which is for games developers.