CHICAGO --Passengers booking flights on United Airlines are getting a reprieve from paying the carrier's fast-rising fuel surcharge due to what United calls a clerical error. The mistake is saving lucky customers as much as $130 round-trip on United's domestic flights -- the airline's maximum fuel surcharge. United spokeswoman Robin Urbanski says the fuel surcharge was eliminated for domestic flights booked Thursday due to a clerical error. The mistake is to be rectified Thursday night. Urbanski says any customer who booked a flight without the surcharge will not be charged for it later. The airfare research site FareCompare.com, which publicized the error, says the surcharge was rolled back as of 12:30 p.m. EDT and would remain absent for any flights booked before midnight.