Sorry for bringing you so much trouble and making you so exasperated.
I don't know which agent you are talking about, but most of them are very friendly and patient. In fact, many customers have sent testimonial to praise them.  You have mentioned in the text one of them even closed the chat when you are talking. It is extremely impolite, even rather rude and is strictly forbidden in this company. Once spotted, a severe punishment will be given. So no one dare to do this on purpose.  Have you ever thought it may be a misunderstanding? Is it possible that she or he just disconnected by accident? I guess, you must have disconnected once when talking with your friends online.
But your feedbacks did sound the alarm! Maybe we just wanted to tell the customers effective ways to solve the problems, but the improper tones or phrases we used misled our customers believing the agents were impatient with your problems or not enough attention has been given to what you really wanted. With no doubt, the systematic learning of speaking courtesy and techniques need to be reinforced in our customer service department.  And we will look into this matter and keep an eye on our agents' daily performance.
Thank you for posting your honest views here and asking the forum for help.
We sincerely apologize for what you have gone through.
Still looking forward to doing business with you in the future.