Vinted users have been reacting angrily due to a modification that led to listings displaying inaccurate size information.
The second-hand shopping app has revised its sizing categories for female and kids' apparel failing to inform all shoppers about the modification.
Many shoppers and sellers are posting online stating that platform listings now display a different size category than originally posted because of the remapping.
The company said the revised method more closely matches comparable marketplaces.
It has advised users to check their listings and update the measurements by hand if necessary, which has left users frustrated.
Earlier, the sizes had both one number and one letter, like S/8 or M/10.
The revised method features an alphabetical indicator and numerical range like S/UK 8-10.
For certain items, the sizing has been recategorised - such as a large size was formerly size 12 but is now a UK 16-18.
One content creator, who makes TikTok content about plus-size fashion, said the change "makes both selling and buying harder".
"Few clothing companies classify XL as 20-22," as the platform currently indicates.
A different member, located in Scotland, said garments she listed featuring size 14 markings were displaying on the service as measurements 20-22.
"If buyers measuring 20-22 acquire them they're going to be very disappointed," she stated.
A different user, located in England, explained she became annoyed because the modification necessitated personal updates the sizes on "every single listing".
"This situation is especially annoying, as I'm chronically ill and Vinted sales have been crucial for me since losing part of my income," she said.
The platform boasts over 100 million shoppers, comprising 18 million UK members.
It has emerged as a preferred choice to second-hand platforms like eBay and Depop.
This isn't the first time when a surprising modification within the service has received backlash: previously, the service retracted a modification to its shipping options due to shopper criticism.
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