Problem with Action Server

edit

Hello, I have this message :

#goal
string start_phrase
---
#result 
geometry_msgs/Point coordinates
---
#feedback
duration time_elapsed

In my server code I have a line like this :

if (self.point!= None and self.point.coordinates.x !=0 ):

and I get this error :

if (self.point!= None and self.point.coordinates.x !=0 ): AttributeError: 'list' object has no attribute 'coordinates'

Why I do not have the coordinates attribute ? I followed this tutorial and from what I have understand I should have had this attribute.