A Quebec woman wound up spending nearly $8,000 in airline tickets to fly herself and her daughter home after Air Canada kicked them off a plane and didn't immediately inform them that they were banned from future Air Canada flights.

Air Canada says the two were ordered to leave their flight, departing Bucharest for Montreal on July 31, because of disruptive behaviour.

Ana Constantin and her daughter, Lisa Maria Paun, deny the allegation, and say that being ousted from the plane was only the beginning of their ordeal.

Because they didn't know at the time about their ban, they booked the next available flight home — the second leg of which was again with Air Canada.

When they arrived at their stopover in Frankfurt, much to their surprise, Air Canada wouldn't let the two board their connecting flight back to Canada, leaving them stranded at the airport.

In all, Constantin, right, racked up more than $8,000 in airfare, hotels and additional expenses trying to get herself and her daughter back to Montreal. (Submitted by Ana Constantin)

"Imagine the frustration," said a still-distraught Constantin from her home in Gatineau, Que. "It's beyond understanding."

Following a CBC News inquiry, Air Canada emailed a letter to Constantin and Paun — two weeks after their initial flight — laying out why they were ordered off that flight and details of their ban.

I am mentally and financially devastated. I cannot eat. I cannot sleep. - Ana Constantin

But the information came too late; Constantin had already paid a total of $7,758 for a flight that only got them as far as Frankfurt, and then another flight on Austrian Airlines to return to Montreal.

"I am mentally and financially devastated," said Constantin. "I cannot eat. I cannot sleep."

Air Canada said it's "dealing directly" with the passengers regarding reimbursement for the Frankfurt flight. So far, Constantin has received a $262.26 refund toward the $3,916 flight.

What are the reasons?

Their troubles began when Constantin, a 45-year old financial officer, and Paun, a 22-year-old university student, boarded an Air Canada flight at the Henri Coandă Airport in Bucharest after visiting family in Romania.

They said the flight's departure was delayed because some passengers had to be reassigned seats so families could sit together.

Paun said someone was assigned to her seat, so she sat elsewhere.

There are contradictory accounts of why the two women were ordered off the plane. Paun said it occurred after she got into a dispute with a flight attendant who asked her to return to her assigned seat, and she replied that she couldn't.

"I said that I can't move back because you just put a man in my seat. And that's when she just got angry with me and said that I'm not co-operating."

Air Canada said the two passengers 'became verbally abusive to the crew' and 'refused to take their assigned seats or safely stow onboard luggage.' (Air Canada)

Constantin said she was in the washroom at the time and when she learned the news, she refused to disembark, so a police officer was called to escort them off the plane.

"We felt very embarrassed and humiliated," said Paun.

Air Canada spokesperson Angela Mah said that Paun and Constantin were removed because they "became verbally abusive to the crew" and refused to take their assigned seats or safely stow their carry-on bags.

She also said, in an email to CBC News, that efforts made by the crew to defuse the situation were unsuccessful.

"Air Canada has a zero tolerance policy for disruption and outright refusal to follow safety directions," said Mah.

What are the rules?

According to Transport Canada, airlines have the right to refuse to board passengers if it's deemed their behaviour may jeopardize the safety of a flight.

But the federal department also says that passengers should be informed about why they're denied boarding and the conditions of their ban.

Constantin and Paun said they received no such information at the time; instead, Paun said a flight attendant told her they'd be rebooked on another Air Canada flight.

The two women spent the next two days in Bucharest, calling Air Canada, but said they were told there was nothing in the airline's computer system about their case.

Desperate to get home, Constantin rebooked them on a flight for Aug. 4, issued by Air Canada for $3,916.

They had no problem boarding partner airline Lufthansa on the first leg to Frankfurt. But then the two women weren't allowed to board their Air Canada flight back to Canada.

"We felt like dirt," said Constantin. "I couldn't take it anymore. I started to cry."

Feeling she had no choice, Constantin shelled out another $3,842 for two seats on an Austrian Airlines flight to Montreal.

In all, she racked up more than $8,000 in airfare, hotels and added expenses, trying to get herself and Paun home.

Entitled to refunds

CBC News asked Air Canada why it allowed Constantin and Paun to book themselves on another Air Canada flight after it had banned them from flying.

The airline responded that anybody can book a ticket and that it's only when passengers check in and show ID that Air Canada can verify if they're prohibited from boarding.

The airline also said that it sent Constantin and Paun information about their ban shortly after they were ordered off the Bucharest flight. However, that information — in the form of a letter — was sent by regular mail and, according to Constantin, hasn't arrived yet. The two women did receive an emailed version of the letter one day after CBC News inquired about the case with Air Canada.

CBC News also asked Air Canada about compensation. The airline's tariff or rule book states that passengers refused boarding are entitled to refunds for the unused portion of their trip.

The airline said that because Lufthansa issued the tickets for the initial Air Canada flight the two women were removed from, it's up to that airline to handle a refund request for that flight.

Air Canada didn't indicate if Constantin will get a full refund for the Frankfurt flight.

Constantin and Paun can try to get their flying ban lifted by writing Air Canada and promising they won't behave badly again. Constantin said she won't be doing that because they have no future plans to fly with the airline.