Thank you for your kind consideration for authorizing xxx to share your personal contact information. Please be assured your information will be handled with utmost confidentiality.

Hi Yi Zhang, What you have written seems perfectly fine, if not slightly informal in my opinion. What you have written is grammatically correct and friendly. If that is the approach you want to take, then go ahead. However, if you wanted something slightly more formal, I would advise you take the "so much" out as it seems a little bit too excited, thus making it less formal. For the same reason I wouldn't include the exclamation mark. A slightly more formal way could be "Thank you for agreeing to share your email address." Although saying this I would like to emphasise again that what you wrote is grammatically correct and it all depends on the approach you want to take. If you have any further questions please feel free to get in touch www.italki.com/maddie. Good luck!

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