OAuth2.0 flow issues (Encountered an error (400)

Hi, I'm setting up an OAuth2.0 authentication flow for the eBay API, when eBay calls back Retool over oauth.retool.com it yields a 400 error. This is the URL that's being called
I'm attaching a few screenshots containing configuration and showing the flow. Any help would be really appreciated. Thanks!


Hey there :wave: Did you follow the flow listed here?