The Messenger of Allah (ﷺ) said:

اَللَّهُمَّ لَا سَهْلَ إِلَّا مَا جَعَلْتَهُ سَهْلًا، وَأَنْتَ تَجْعَلُ الْحَزْنَ إِذَا شِئْتَ سَهْلًا

Allaahumma laa sahla 'illaa maa ja'altahu sahlan wa 'Anta taj'alul-hazna 'ithaa shi'ta sahla

O Allah, there is no ease other than what You make easy. If you want you can make difficult matter easy.

Reference: Sahih (Ibn Hazar Asqalani). Ibn Hibban: 974