'I flew 5,500 miles and paid £900 for a Premier League ticket but was turned away'

For some football fans, attending Premier League matches is a weekly habit. They purchase their season tickets for home matches and travel the country following their team away, too.

For others, going to a game in England's top tier is a once-in-a-lifetime opportunity which they save up and take extended time away from their regular lives for.

Last weekend James from South Korea travelled 5,500 miles to Brighton watch his beloved Tottenham play for the first time, paying £900 for a ticket from an unauthorised resale website. When he tried to enter the stadium, he was turned away.

After the BBC exposed the industrial-scale black market in Premier League tickets last week, Brighton invited us along to demonstrate how widespread the problem is, and how they are trying to combat it.

The ticket James purchased had already been deactivated when he tried to scan it to enter the Amex stadium. He was advised to go to the ticket office, where Brighton staff then informed him that his ticket had been purchased illegitimately.

"I'm disappointed, I didn't understand this rule," he said outside the stadium, visibly upset.

"I have been told I should try and get a refund for the ticket."

More than a hundred more like James also had their tickets for the match cancelled in the same way.

Reselling is against UK law but many websites continue to operate by being based outside the country.

The BBC's investigation found that resellers often use bot software and fake identities to hoover up hundreds of tickets to be sold on for higher prices, and can leave fans paying extortionate prices or completely out of pocket after buying tickets that don't work.

"Long-term supporters are finding it impossible to get tickets because of the way they are made available through secondary agencies," says Tom Greatrex, chair of the Football Supporters' Association.

"This is becoming endemic across the game."

Brighton say they are using new technologies to try and crack down on the reselling of tickets for vastly inflated prices by unauthorised websites.

To try and get a grip of the problem, this season they hired Joseph Sells into a new staff position as tickets investigation officer, and he was on duty for the Tottenham fixture.

"We've found hundreds [of unauthorised resale tickets] today, and going at the black market rate, we've prevented around £100,000 of transactions that would have been going to touts," Sells said.

"We're investing heavily in stopping the problem at the core, using the latest tech we can, and we're on top of it.

"A family came with six tickets to watch the Manchester City match a fortnight ago, which they had paid a total of £6,000 for.

"That's very upsetting of course. It's a sad story, but that's why we're reiterating - if you want to come and see a game, buy directly from the club."

Brighton later told the BBC that 285 touted tickets were blocked at the match, and that 12 individual season ticket holders were also identified as touts and have had their tickets for future matches cancelled.

One of the tout accounts used the name Tony Montana - the lead character in '80s gangster film Scarface - to try and bulk purchase tickets.

The Premier League is already introducing new rules for digital ticketing which include the introduction of encrypted barcodes, which they say will make touting more difficult.

Sells explains that, while he shares resources with other clubs, the software is bespoke to Brighton and searches for suspicious transactions and scours resale sites for any tickets listed with seat numbers.

"We're essentially training a model to spot tout behaviour before it can come into the club," he says. "It applies a risk score to each transaction.

"Let's say someone in Estonia is shopping with a prepaid card issued in the United Arab Emirates - that is going to flag the system.

"The model learns every day how to spot more anomalies."

At Brighton, fans presenting an unauthorised ticket to staff are given a letter which explains what has happened and concludes with the sentence: "To obtain a refund you should contract your card issuers who will assist you as a victim of fraud in reclaiming monies you have paid to the seller."

The club also offers any remaining seats in the stadium - either from season ticket holders unable to attend or in hospitality sections - for sale to fans whose tickets are blocked on entry.

For some of those like James who believe that resale websites are helping them fulfil their dream of attending a game, matchday can turn into a nightmare.