Hello @Sreenivas Reddy ,
Thanks for reaching out and apologies for the delayed response.
I was unable to open the URL you mentioned. However, based on your query, I believe you are trying to add apple IDP to Azure AD B2C but get an 'invalid client' error while connecting.
To better assist you in this scenario, I would recommend that you setup and collect Azure Active Directory B2C logs with Application Insights and share the detailed error message along with the correlation ID and timestamp. Also, if possible, could you please share the link that you are referring to again?
I'd like to share some similar threads for your reference just to make sure we have everything set up correctly.
Hope this helps.
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