diff --git a/pnut-bridge.py b/pnut-bridge.py
index 586eadb..71fe894 100644
--- a/pnut-bridge.py
+++ b/pnut-bridge.py
@@ -78,11 +78,14 @@ class ChannelMonitor(threading.Thread):
 
     def invite_room(self, user_id, roomid):
         url = self.matrix_api_url + '/rooms/' + roomid + "/invite"
+        headers = {"Content-Type": "application/json"}
         params = {
             'access_token': self.matrix_api_token,
+        }
+        body = {
             'user_id': user_id
         }
-        r = requests.post(url, params=params)
+        r = requests.post(url, headers=headers, params=params, data=json.dumps(body))
 
     def send_message(self, roomid, msg):
         url = self.matrix_api_url + '/rooms/' + roomid +'/send/m.room.message' + '/' + str(self.txId)