Option 1

Speak directly with the airline's customer service representative at the airport, explaining the urgency and asking for any possible solutions, even if it involves a fee.

Option 2

Call my manager immediately to inform them of the error and suggest they contact the airline on my behalf, emphasizing the importance of my presentation.

Option 3

Accept the loss, cancel the flight, and try to find an alternative, more expensive last-minute flight or a different way to attend the conference virtually, hoping my manager understands.