A Nashville woman says a Southwest Airlines policy left her scrambling at the airport and nearly caused her to miss a cruise she had planned. Ruby Cosby had flown Southwest for years without incident, but a February trip to Los Angeles changed everything.

On Feb. 28, Cosby arrived at the gate for her flight to LAX when a Southwest agent stopped her from boarding. The agent told her she would need to purchase an additional seat, citing a new company policy that took effect on Jan. 27. That policy requires customers who encroach on neighboring seats to purchase as many seats as needed. The extra ticket would cost $450.

Cosby said she was caught completely off guard. She had bought her original ticket before the new policy went into effect and had no idea the rules had changed. She also said she had never had a problem fitting in a seat before.

“I can fit in the seat like I have fit in the seat with no problem for many years,” Cosby said. She asked if she could simply try sitting in a seat before being turned away, but the agent refused, telling her that walking her to the gate only to find out she could not fit would create a bigger disruption.

Because she did not have the extra $450 on the spot, the agent canceled her existing ticket. Cosby called her family from the airport, they sent her money, and she went to rebook. When a different agent started processing her ticket without requiring the second seat, things seemed to be turning around. But when Cosby mentioned her already-checked bags, the original agent stepped back in and told her she still needed to buy two seats.

To make things worse, Southwest told her the credit from her canceled ticket could not be applied right away because basic economy fares are non-refundable. She would have to wait for a refund and rebook separately.

Cosby ended up buying a one-way Delta ticket to LAX for $350 and made her cruise. She received a credit for the canceled Southwest ticket, but it expires in July.

Southwest responded to the story with a statement saying the policy changes were communicated nearly a year in advance and are consistent with industry standards. The airline added that it has reached out to Cosby directly to address her concerns.

Cosby said she has not heard from Southwest since the incident. Her bigger concern is not the policy itself but the way it is applied.

“I feel like this policy can be used unfairly because there’s not guidelines,” she said. “It’s just based off of perception.”