HttpUtility is not declared, It may be inaccessible due to its protection level

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1

I am trying to parse email address. But i keep getting "httputitlity is not declared error.

varRealtor1href = javascript:openContactMe(‘https://www.mlsli.com/Content/Forms/ContactMe.aspx?listingagentid=10903990&agentemailaddress=raj@rajhasbuyers.com&subject=Inquiry:%20Listing%20No.%203213038&FormID=2&AgentFlg=1&BRListingFlg=0&ListingSourceID=436&ListingID=295840218&WebsiteID=1016805&IsWebsite=1&IsPrimary=1’);

varRealtor1URL = new Uri(varRealtor1href)
varAgent1EmailAddress = HttpUtility.ParseQueryString(varRealtor1URL.Query).Get(“agentemailaddress”)

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