What should I do to atone for my oath, as I swore to attend a match but did not, due to a power outage?

Whoever swears to do something, and then the object of the oath becomes impossible due to a normal impediment that occurred after the oath, has broken their oath and must offer expiation. The expiation for breaking an oath is: feeding ten poor persons with an average meal, or clothing them, or freeing a slave. If one cannot do any of these, then they must fast for three days.