PHOENIX — UPDATE: ABC15 has updated the headline of this story to reflect that Kai is an Emotional Support animal rather than a service dog.

An airline's controversial ban on pit bulls as service animals has left one man and his dog stranded here in the Valley.

Zachary Smith says he had no problem boarding a Delta flight from Cincinnati to Phoenix, but now the airline will not allow his dog on board, citing a ban on pit bulls.

Smith said when airline staff in Ohio told him to show up at the airport and to ask to speak to a manager - he did just that and was allowed to board in Cincinnati.

Smith showed ABC15 a picture of his 3-year-old Emotional Support animal Kai, wedged between his legs on the flight. Smith said Kai was still for most of the flight and only got up a couple of times to get a small drink of water.

"He's very well trained and well mannered and gets along with everybody," said Smith.

He expected to have no problems when he showed up at Phoenix Sky Harbor airport to board his return flight on Thursday.

Smith said he asked to speak to a Delta "red coat" manager and was denied entry on to the plane because his dog was considered "a dangerous and aggressive" breed.

Smith who suffers from anxiety said he felt humiliated by the experience.

He pointed out that the US Department of Transportation has questioned the ban of service animals by airlines.

In a statement, federal officials said "a limitation based exclusively on breed of the service animal is not allowed under the Department's Air Carrier Access Act regulation."

The agency did not say whether it had communicated with Delta officials about this interpretation of the federal disability law that applies to air travel, but it suggested that passengers turned away from flights would need to file a disability complaint with the department.

"I would just say you know understand the demeanor of the dog, not just the breed of the animal," said Smith.

ABC15 reached out to Delta airlines. A spokesman said they had reimbursed Smith for the return leg of his flight.

Delta also sent us the following statement:

"We apologize to this customer for their experience while attempting to travel with an animal that did not meet our service and support animal policy.

Delta continuously reviews and enhances its policies and procedures for animals onboard as part of its commitment to health, safety and protecting the rights of customers with disabilities. In 2018, Delta tightened its policies on service and emotional support animals, which included a ban on pit bull-type dogs as service or support animals. These policy updates reinforce Delta’s core value of putting safety first, always.”

Smith said he planned to file a complaint with the Department of Transportation and was now hoping to head back east by hitching a ride with a friend.

Delta officials say you can read their full policy here.

Smith and Kai boarded a United flight back to Ohio on Saturday, December 28. He sent ABC15 a photo after they were settled in their seat.

GREAT NEWS! Zachary Smith just sent us this photo after he and Kai boarded a United flight home. #abc15 pic.twitter.com/lKeoQQOVoL — ABC15 Arizona (@abc15) December 28, 2019

The airline seemed to have no issue with the breed of his dog when he informed them while reserving his flight, he told ABC15.