Getting following error when requesting for remote authorization 

Sending ts as 

var ts = (Int64)(DateTime.UtcNow.Subtract(new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc))).TotalMilliseconds;

APIKey:

var apikey = hexdigit(md5Of(operation + email + loginName + fullName + utype + remoteAuthKey + ts));