Answer:
There is a problem at the lab that he works at so he has to rush there.
Book: What if it's us by Becky Albertalli and Adam Silvera
It is a LGBTQ+ novel about two boys who meet by so-called "fate" The book offers both boys perspectives throughout the story. Arthur moves to NY and believes in fate, love at first sight, and all that stuff. He believes people are brought together for a reason. Ben on the other hand lives in NY, and believes that the universe is out to get him, and that he has bad luck with all of that. He doesn't believe in fate. The story progresses where they are both in NY and don't know each other. They meet at the post office and their paths intertwine....
The answer to this question would be "Technological unemployment" I hope this helps.