squander (someone's) chances

Translations
упустить (чьи-то) шансы
He squandered his chances of getting the promotion by not preparing for the interview.
Он упустил свои шансы на повышение, не подготовившись к собеседованию.
Definitions
To waste or misuse opportunities or favorable circumstances that someone has been given, often resulting in regret or lost potential.