Vinted users have been reacting angrily after an update resulted in listings displaying inaccurate size information.
This online marketplace has altered its sizing categories for women's and children's garments without notifying all users about the change.
Many shoppers and sellers are expressing on platforms saying Vinted listings now show a different size category than originally posted because of the remapping.
The company said the new system was more in line with comparable marketplaces.
It has advised users to examine their items and manually change the size if necessary, resulting in member annoyance.
Earlier, the sizes had both numerical and alphabetical indicators, such as S/8 or M/10.
The new system has an alphabetical indicator and numerical range like S/UK 8-10.
With some products, the measurements have been reclassified - like an L measurement used to be a 12 but now shows as UK 16-18.
Frankie Bridger, who produces content about larger sizing, explained the modification "makes transactions more difficult".
"Not many brands say XL is a 20-22," the way the service now categorizes.
Another user, located in Scotland, explained products she uploaded featuring size 14 markings were showing in the marketplace as measurements 20-22.
"If anyone [who is] size 20-22 buys them they're going to be very disappointed," she said.
Charlotte Lunn, located in England, stated she felt frustrated because the modification necessitated personal updates the sizing for "all her products".
"This situation is especially annoying, because of my ongoing medical condition and Vinted sales have been crucial for me since losing part of my income," she said.
The service features exceeding 100 million users, including 18 million in the UK.
It has become a favored option versus similar marketplaces including eBay and Depop.
This isn't the first time when a surprising modification on the platform has faced criticism: previously, the platform withdrew an update to its shipping options after backlash from users.
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