"due to a scheduling conflict" is correct and can be used in written English. It is used to indicate a reason why something cannot be done or why a change in plans was necessary. For example: "I'm sorry, I won't be able to attend the meeting due to a scheduling conflict.".
Due to a scheduling conflict, the chat has been postponed.
"It was postponed due to a scheduling conflict," said James Jordan, the committee's executive director.
Cotillard has been forced to quit production of the untitled project due to a scheduling conflict.
** UPDATE: This chat has been cancelled due to a scheduling conflict.
UPDATE: This chat has been cancelled due to a scheduling conflict.
However, Hung declined due to a scheduling conflicts.
(I was not able to attend the Zep event in person, due to a schedule conflict).
Being a terminologist, I care about word choice. Ludwig simply helps me pick the best words for any translation. Five stars!
Maria Pia Montoro
Terminologist and Q/A Analyst @ Translation Centre for the Bodies of the European Union