be set in your ways

be set in (one's) ways

To be habituated to one's routine or usual behavior, often to the point of being unwilling to change any aspect of it. Grandma will never retire—she's been a teacher for 50 years and is totally set in her ways. You'll never convince him to change, he's too set in his ways now.
See also: set, way

be ˌset in your ˈways

be unable or unwilling to change your behaviour, habits or ideas, usually because you are old: He’s too set in his ways now to think about a career change.
See also: set, way