stubborn
stub-born
adjective
Unwilling to change one's opinion or course of action despite good reasons.
"She was too stubborn to admit her mistake."
Thesaurus
Synonyms: intractable, refractory, mulish, pigheaded, contrarious, dogged, tenacious, unregenerate, bolshy, hardheaded, cross-grained, persistent
Antonyms: docile