Message":"Bad Authentication data","code":215


#1

I am trying to send direct_messages/new to my friend using c# but i am enable to send data … I used this POST Call this this URL:
https://api.twitter.com/1.1/direct_messages/new.json?text=crowdblood&user_id=465xxxxxx?oauth2_access_token=" + accessToken; but it giving following Error .

“Bad Authentication data”,“code”:215

Can any One Help Me
Thank you,
T.R.K