Eruss1088, where are you? You’re getting all sorts of input – has anything worked or changed since your initial post?
Thank you all for the input!
After going through all of your input, I decided to take him out on a trail ride instead of working him in a round pen and only try a few strides of canter. He was slow at first ad to understanding what I was asking for but in 5 minutes we were doing cantering transitions. I focused more on balancing my seat and allowing him to canter.
I had talked to the person who trained him when i had gotten him and we have frequent lessons with her but even when I am on top of him on a lunge line he goes right into an extended trot. By the end of the lesson it takes him about 30 seconds to transition into a canter and doesn’t rush off so much.
Most of you reminded me that i had a nasty habit of not keeping my hands soft while asking for the canter so I gave him his head (for now) while asking and that seemed to help a little bit as well. I also had a saddle fitter come out to check out the saddle and she said that it fit like a glove but suggested that his back might be sensitive and to put a gel-pad under it. When I did and we went for a ride he seemed perkier and willing to move forward.:yes:
I am going to keep trying all of these ideas and advice you have provided me with. I have come to find out that he has been out of work for over a year so he is a bit rusty.
Whereas when I had acquired him, I was told he hadn’t been riding for only a couple months. So this too i have taken into consideration and am strictly working on his stamina and muscle building before we continue any further with the canter.
Once again thank you all so much for your advice and input! It has helped tremendously! 
Sounds like you are making progress. If you are trying to canter in a roundpen, that may be making your problem worse. I find they are too small for an out of shape horse to feel comfortable and maintain balance more often than not.
If you want to work on it, do so in a ring where you have a nice long straight side to canter up without worrying about bend/circle.
^ This. Round pens are overrated, especially for large warmbloods.
