"I had something come up," maybe

FIB

A little white lie might explain why someone suddenly canceled plans.

The phrase "I had something come up" is often a vague excuse people use when they don’t want to admit the real reason for canceling plans. In crosswords, "maybe" hints that the answer isn’t literal but a playful stand-in—here, it’s "FIB," a short word for a small lie or excuse. The clue works by treating the common expression as a lighthearted deception, matching the definition of a fib.