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Welcome to the forum.

i'm not sure that i'm missing.

You're missing at least providing information.

Just posting "it doesn't work" is really useless.

Please, post question that can be understood. Otherwise, don't expect any help.

You should read and apply advices from this post https://developer.apple.com/forums/thread/706527 and then reformulate your question.

When precisely do you get this error ?