Can FaceBook Access Token be reused

this is the error

The remote server returned an error: (400) Bad Request.

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. Exception Details: System.Net.WebException: The remote server returned an error: (400) Bad Request. Source Error:

Line 28:                     //Labelwelcome.Text = faceBookUser.Name;
Line 29: 
Line 30: string data = FaceBookConnect.Fetch(code, "me/friends"); Line 31:                     //Response.Cookies["name"].Value = id;
Line 32:                     FaceBookData facebookData = new JavaScriptSerializer().Deserialize<FaceBookData>(data);