incompliant

adamant adamantine balky brassbound bullheaded cantankerous contumacious cussed determined die-hard dogged firm fixed grim hardheaded headstrong implacable inexorable inflexible insubordinate intractable intransigent iron mulish obdurate opinionated ornery persevering persistent pertinacious perverse pigheaded rebellious recalcitrant refractory relentless remorseless rigid self-willed set in one's ways single-minded steadfast stiff-necked tenacious tough unbendable unbending uncompliant uncompromising unmanageable unreasonable unrelenting unshakable untoward unyielding willful