throw in the towel
US /θroʊ ɪn ðə ˈtaʊəl/
UK /θroʊ ɪn ðə ˈtaʊəl/

1.
to give up or admit defeat
:
•
After losing three games in a row, the team decided to throw in the towel.
•
Despite the challenges, she refused to throw in the towel and kept fighting for her dreams.