rest on your laurels
US /rɛst ɑn yʊər ˈlɔrəlz/
UK /rɛst ɑn yʊər ˈlɔrəlz/

1.
to be satisfied with your past achievements and not to make any further effort
:
•
After winning the championship, the team decided not to rest on their laurels and started training for the next season.
•
He's a talented artist, but he tends to rest on his laurels instead of exploring new styles.