Cher has hit out at Fabletics, the athletics clothing website that was founded by actress Kate Hudson.
The singer, 70, claimed she made the 'mistake' of visiting the subscription retailer, while bemoaning not being able to 'see anything' on the site at all while browsing.
The Turn Back Time hitmaker added that she felt she was 'being conned' by Fabletics, which is a subsidiary of fashion retailer JustFab.
"Made mistake of going2 Fabletics.What a pain in the ass.won't even let u see anything Till u give them ur 1st born!! Felt I Was Being Conned," she wrote to her three million Twitter followers on Monday.
Kate, 37, co-founded Fabletics with Adam Goldenberg and Don Ressler in 2013, bringing her own line of stylish active-wear - which she models herself - to the hotly-contested sportswear market.
Cher appears to have been disappointed by the website's sign-up service, which sees prospective customers have to answer a questionnaire in order to be able to see sportswear that has been chosen specifically to suit them.
Fabletics responded directly to the singer via Twitter, writing: "We LOVE you @Cher! Please know our quiz is to personalize shopping and so we can eliminate waste by only creating clothing people want."
And, speaking to PeopleStyle, JustFab corporate marketing officer Shawn Gold said: "First of all, we love Cher! We're so bummed she did not like our member quiz.
"The introductory quiz helps us better understand our customers and personalise the shopping experience. By asking shoppers for their style and size preferences, we're able to save our customers tons of money and eliminate waste.
"We only produce the clothing that people want. I wish we could turn back time and explain this to Cher."
Shawn went on to add that the brand consistently works on listening to feedback from over one million members.
"We regularly introduce new ways to enhance the experience of our shoppers. Recently we've expanded customer service to 24/7 support and added video in the shopping cart to further explain the membership programme.
"We also added online cancellations to ease the process when customers change their minds about how they'd like to shop with us. We get very few complaints relative to the number of customers we have, but all complaints are upsetting to us. So we do everything we can to ensure our customers are happy."
Questions in the member quiz include asking for a client's particular workout preference (whether that's running, yoga or the gym), colours that "get you moving" and their body shape.
The customer is then taken to a shopping page of different sporty ensembles based on their specific needs, offering up a variety of outfits and gym-appropriate separates.
One must sign up to become a member and pay £44 per month (after the initial sign-up fee of £20) to be able to shop for new styles: the site also claims customers "will save up to 50% off regular pricing and earn points towards free loyalty items".
The retailer also offers the chance for subscribers - or "VIP members" - to "skip the month" if they so wish, giving them the choice to opt out of paying for a month at a time.