to go back on a promise
[go] back on {one's} promise[go] back on {one's} deal[go] back on {one's} pledgeto go back on a promise
01
to fail to keep or fulfill a commitment or assurance made to someone
Collocation
例子
She went back on her promise to help with the charity event.
The politician went back on promises made during the campaign, disappointing voters.
