dig heels in

dig (one's) heels in

To cling stubbornly to one's beliefs, position, or wishes. Please let me tell my side of the story before you dig your heels in on this, OK? I told Grace she can't go, and now she's dug her heels in as if this party is the most important thing in her life.
See also: dig, heel
Farlex Dictionary of Idioms.

dig one's heels in

Fig. to refuse to alter one's course of action or opinions; to be obstinate or determined. The student dug her heels in and refused to obey the instructions. I'm digging in my heels. I'm not going back.
See also: dig, heel
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.
See also:
  • dig (one's) heels in
  • dig your heels in
  • dug
  • dig in (one's) heels
  • dig in heels
  • dig in your heels
  • dig (deep) into (one's) pocket(s)
  • dig down
  • dig (something)
  • dig this