固执 (gù zhi): 頑固な

He is too obstinate; even though he clearly took the wrong road, he refused to look at the map and wouldn't listen to others' advice.

Grandpa stubbornly insists on taking a cold shower every morning; no matter how much the family tries to persuade him, he won't change, saying it's good for his health.

She stubbornly believes her own method is the best and refuses to try new software, so her work efficiency ends up much lower than others'.

During the negotiation, he was stubborn and refused to give an inch, causing both sides to be deadlocked for several hours.

The child stubbornly insisted on buying that toy, lying on the floor crying and throwing a tantrum, so the mother had to take him out of the store first.

Don't be so obstinate; listen to your colleagues' suggestions—maybe you can find a simpler solution.