Assalamualaikum
In Fortress of the believer, you'll find some dua also about making things easy generally not specifically for this.
In the Fortress of the Muslim, there is a du'a in Chapter 43: Invocation for when you find something becoming difficult for you, page 119.
The dua is:
اللهم لا سهل إلا ما جعلته سهلا وأنت تجعل الحزن إذا شئت سهلا
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Allahumma laa sahla illa maa ja'altahu sahlan wa anta taj'alaul-hazna ithaa shi'ta sahlan.
"O Allah, there is no ease other than what You make easy. If You please You ease sorrow."