Just because you define a label one way does not mean that other people have to accept or adopt your label. If a non-binary person doesn't want to identify as trans, do not force that label on them.

Also this statement is coming from a very western perspective. There are more than two genders in the world and there are civilizations which recognize and support genders outside the binary. Some people are not assigned gender at birth in the society they were born in, and in some civilizations their gender does match what was assigned to them by society and that identity is neither male nor female, but something else.