My wife and daughter are mid-itinerary on an award reservation in South America.

My wife needs emergency dental work, and I need to rebook her a later return.

On Friday, I rebook on the website for different dates.

I select flights that the website says are the same, or fewer, miles than the original tickets.

The tickets reissue on Friday. No problemo. Wife makes plans for a root canal plus.

On Monday, my wife gets an e-mail from United stating that the rebooking did not cost the amount of miles the website stated. The e-mail says that her ticket costs 25,000 additional miles and will be rescinded because the extra cost in miles resulted in her MP account balance going negative. Wow, I never knew you could book yourself into negative miles ... and why didn't the website say this?

While I consider this a bait and switch, booked at one price and then switched to another, an agent seems to think that United "caught" me trying to defraud them. All I did was rebook the tickets on the website, clicking the blue saver award icons.

The agent says they will cancel the reservation unless we pay $500 to buy more miles.

Whaat? Pay $500 on Monday for a reward ticket that was issued without incident, and for existing miles, on Friday?

To make a long story short, I had to spend all morning talking to about 6 people at United to try to work this out. Multiple callbacks after getting abandoned on hold.

Until the very end United would not squarely acknowledge that their website made a mistake and United would not step up to the plate to either allow the itinerary to proceed or to propose some reasonable alternative.

I finally found a similar itinerary at a lower mileage level, and they "kindly" waived the change fees (since she's just a regular member and we're now under two weeks). The last agent I talked to was reasonably nice about it.

But what an awful experience. Complete bait and switch on the rebooking, and an almost complete refusal by anybody reachable on the phone to acknowledge that the error was theirs, and the only reason why this messed up situation existed was because the website apparently stated the wrong number of miles for a ticket change, and allowed that change to happen, despite the miles not existing in my wife's account.

Big thumbs down to United.