Chris Vallance is a writer.
Technology reporter
A watchdog ruled that a web page and a Facebook post by the football club broke advertising rules.
The club failed to demonstrate the risk of the investment according to the Advertising Standards Authority.
The form complained about the ads and they must not appear again.
An independent review of the ruling will be sought by the club, it said.
Several football clubs give fans token.
Critics say that clubs that promote fan token are encouraging people to invest in the unregulated world of cryptocurrencies.
The two promotions of the fan token were ruled against.
The first violation was focused on the official website of the club, with the title '$AFC Fan token: Everything you need to know'.
The club's official Facebook page posted a question on what song fans would like to hear when they win, which was the second violation. You can get your token and vote with the Socios app.
The post and website text were investigated by the ASA.
They took advantage of consumers' inexperience and trivialised their investment in thecryptocurrencies.
They failed to show the risk of the investment.
It said that the Facebook post did not make clear that the token was only available by opening an account and exchanging with another currency.
The website and the Facebook post broke the rules and the ads must not appear again in the form complained about, according to the watchdog.
In the future, the club must make it clear that the value of fan token investments was variable and that they were not regulated.
The club takes its responsibilities with regard to marketing very seriously.
We provided information regarding financial risks to fans.
The Club said it would be seeking an independent review of the ruling of the ASA.
In defending its marketing, the club argued that fans could lose some or all of their money.
It said the marketing material said to only spend what you can afford and seek independent financial advice.
The Club argued that the fan token was not promoted as an investment and that they did not encourage trading of them.
The first club to be judged to have violated advertising standards was the Gunners.
It is one of a number of clubs that have joined forces with a company called Socios.
Socios told the Tech Tent that it has sold hundreds of millions of coins through its app, but wouldn't say how much money goes to clubs it works with.
Socios welcomed the call for an independent review. This is a fast- moving area and clarity is needed to ensure that all companies are following the guidelines.
The more fans collect, the more influence they can have on the running of the club.
Fans have to use a currency called Chiliz to buy and sell fan token, the exception being free non-tradeable fan token.
In the five major European leagues, 24 clubs have launched or are considering launching fan token.
Digital collectibles, known as NFTs, are sold by some clubs. In September, French firm Sorare, which sells football trading cards in the form of NFTs, raised $680m in funding.
Some supporters groups are cautious. In August, the trust said the club should make it clear that the activity is risky.
The board member of the Trust told the BBC that clubs should not be allowed to use football's popularity to push an inherently high-risk product.
The Trust believes that the government and football authorities should look into partnerships between clubs and companies.
If they are to continue, then a greater effort must be made to inform fans of the downside of buying token.
The Advertising Standards Authority is concerned that many ads fail to fully convey the risks of investing and that is a red-alert priority.
The authority's chief executive told the radio station that the public was not aware of the risks of thecryptocurrencies and that they were unregulated.
He told consumers to be very careful before buying. Do you know enough about cryptocurrencies? Can you afford to lose what you've spent?
In the new year, the watchdog plans to issue guidance on marketing of cryptocurrencies, and will continue to publish rulings on ads.
Advertising standards authority
NFTs.
It is a form of money called cryptocurrencies.
