re: "How can I change my response to client feedback? Is there any option for that?"
There is no button you can click to change your response to client feedback.
For future reference, follow this general rule:
Don't respond to client feedback.
Goran V wrote:
Yes clients and freelancers can enable each other to change the feedback they have provided on the contract.
That does not include the response though. It is his own response he wants to change, not the feedback he left.
This is not possible, but Support can remove it for him entirely if that is what he wants to do (it would be wise).