My stupid theory:
If the car didnt break down, They wouldn't get out of the car. 😭
If they didnt get out of the car, They wouldn't be soaked in the rain. 😛
If they weren't soaked, Devu wouldn't be in a naughty mood. 😳
If Dev weren't to be naughty, Kaju wouldn't get out of the car. 😆
If Kaju didn't get out of the car, Dev wouldnt follow her. 😉
If Dev didnt follow her, He wouldn't lend her his jacket.
If he didn't lend her his jacket (which had the cellphone)... 🤢
All this wouldn't happen! 😕
..So in the end, the car is to be blamed! 😡