Thank you for your question
My name is ***** ***** I shall do my best to help you.
You will need to make the application to the Court in Canada to change/dismiss the Child Support.
The English courts can only deal with the enforcement
Please ask if you need further details
Sorry - do you mean dealing with the Canadian courts?
I am sorry I am a Uk lawyer - you would need to ask the Canadian Law section for assistance with that I am afraid