unflexible
/ʌnˈfleksɪbəl/Definitions
1. adjective
Not capable of bending or being changed; inflexible in attitude or opinion.
“Her inflexible stance on the issue made it difficult to find a compromise.”
2. noun
A person who is not willing to change their opinion or attitude.
“The team’s unflexible captain refused to adjust their strategy during the game.”