That is from the news of the unseen which We reveal to (3:44)

﴿ذَٰلِكَ مِنْ أَنبَاءِ الْغَيْبِ نُوحِيهِ إِلَيْكَ ۚ وَمَا كُنتَ لَدَيْهِمْ إِذْ يُلْقُونَ أَقْلَامَهُمْ أَيُّهُمْ يَكْفُلُ مَرْيَمَ وَمَا كُنتَ لَدَيْهِمْ إِذْ يَخْتَصِمُونَ﴾
[ آل عمران: 44]

3:44 That is from the news of the unseen which We reveal to you, [O Muhammad]. And you were not with them when they cast their pens as to which of them should be responsible for Mary. Nor were you with them when they disputed.

The story of Zachariah and Mary is one of the reports of [ the Ghaib ] which I reveal to you, O Messenger.
You were not there with those scholars and worshippers when they argued about who was most entitled to raise Mary.
They eventually decided to draw lots by throwing their pens, and the pen of Zachariah ( peace be upon him ) won.

This is a part of the news of the Ghaib (unseen, i.e. the news of the past nations of which you have no knowledge) which We inspire you with (O Muhammad SAW). You were not with them, when they cast lots with their pens as to which of them should be charged with the care of Maryam (Mary); nor were you with them when they disputed.

phonetic Transliteration

Thalika min anbai alghaybi nooheehi ilayka wama kunta ladayhim ith yulqoona aqlamahum ayyuhum yakfulu maryama wama kunta ladayhim ith yakhtasimoona

Abdullah Yusuf Ali - Translation

This is part of the tidings of the things unseen, which We reveal unto thee (O Messenger!) by inspiration: Thou wast not with them when they cast lots with arrows, as to which of them should be charged with the care of Mary: Nor wast thou with them when they disputed (the point).

Safi-ur-Rahman al-Mubarakpuri

This is a part of the news of the Ghayb (Unseen) which We reveal to you. You were not with them, when they cast lots with their pens as to which of them should be charged with the care of Maryam; nor were you with them when they disputed.

Page 55 English transliteration