Hey there,

It seems that I can't replicate the issue that you mentioned as I am able to sign in to your site with my Linkedin account.

Can you provide us the Linkedin Account and password which will come out with this error?

If cannot, can you screenshot each of the My Apps from https://www.linkedin.com/developer/apps which are Authentication, Settings, Roles, Mobile, JavaScipt, OS and Usage & Limits so we can have a further check on it? (Kindly refer the screenshot)