Du'a using Allah's Name Al-Waahid

اللَّهُمَّ يَا وَاحِدُ فَرِّجْ كَرْبَنَا وَغَمَّنَا

Allahumma ya Waahidu farrij karbana wa ghammana

O Allah, The One, relieve our anguish and distress.

A general supplication, not a narration from the Prophet (peace be upon him).