Post will not update after checking off Amazon Polly Setting

If I try to Enable Amazon Polly on a post I encounter two issues. I am not able to preview the post also if I try to update post after enabling Amazon Polly through the post check mark screen it takes me to a white page with following url sitename/wp-admin/post.php. So basically post never gets saved and Amazon polly never gets enabled. Any thoughts on what the issue could be.

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