boyunu aşan

listen to the pronunciation of boyunu aşan
التركية - الإنجليزية
out of one's depth
To be in a situation which one is poorly prepared or unprepared to handle

The team's first game was against the league champions; they were out of their depth and knew it.

To be in water so deep that one cannot stand up and a may be at risk of drowning. http: //www.yourdictionary.com/idioms/out-of-one-s-depth