Effectively I have contructed a socket TCP in order to connect to Ubidots, because everything is in ladder structure and PLC's are a bit restrictives about sharing data to a third-party it was difficult but I took some of your advice and now I have done everything.
I was not getting the feedback message because I had the line " Connection: close " in my code (I took this example from Get Started) so I deleted and worked.
By the way, my PLC doesnt support JSON just ASCII data, and I am not able to parse anything but successfully I jumped over those things in order to get the information I needed.
As I had opened this topic I may say that it can be closed now,
Thank you for all your support, see you next time.