Comedian Leigh Francis says fake versions of the charity t-shirt he made following the death of his friend Caroline Flack are being sold online.
The actor – better known as Keith Lemon – accuses other people of “ripping off” his design, which he made to support The Samaritans.
And he’s urging websites remove the fakes to make sure as much money as possible goes to charity.
So far, more than 11,000 of his original Be Kind tees have been sold.
Caroline took her own life earlier this month and Keith had known her for years.
Launching his t-shirt, he said he wanted to spread her #BeKind message – and said all the profits would go to charity.
But fakes have started springing up online.
Radio 1 Newsbeat’s found a number of sites selling the fakes – originals can only be purchased through Keith Lemon’s own pages.
And the comedian’s put out a number of messages on Instagram, urging people not to buy the copies.
“Thanks so much to everyone who’s bought a t-shirt for Be Kind. Unfortunately, there’s a website called Teespring.com that’s ripped off the design and unless they’re going to give that money to The Samaritans, then they’ve stolen my design and taken that money that would’ve gone to The Samaritans,” he said.
He then posted another message to say the company had removed the fakes.
Teespring has since apologised, saying all designs are created by “independent individuals”. It also says the user’s account has been “disabled” and that it “doesn’t support this behaviour”.
The company hasn’t said whether it’ll be handing over any profits to charity – but fakes are turning up on a number of other sites too.
Newsbeat has contacted several of the sites selling fakes but so far, there has been no comment.
If you are affected by any of the issues raised in this article and want help or information you can visit BBC Advice.