Shoppers are voicing their frustration due to a modification that led to items being listed as the wrong size.
This online marketplace has revised its size classifications for women's and children's clothes without notifying all users about the change.
Many shoppers and sellers are posting online stating that platform listings now display an altered size classification compared to what was initially listed because of the remapping.
The company said the revised method more closely matches other platforms.
They have suggested members to examine their items and update the measurements by hand if necessary, which has left users frustrated.
Earlier, the sizing featured numerical and alphabetical indicators, such as S/8 or M/10.
The revised method features an alphabetical indicator and numerical range for example S/UK 8-10.
In some cases, the sizing has been recategorised - like an L measurement was formerly size 12 but now shows as UK 16-18.
One content creator, who creates plus-size fashion videos, said the change "makes both selling and buying harder".
"Not many brands say XL is a 20-22," which is what Vinted now does.
Another user, based in Glasgow, explained products she uploaded featuring size 14 markings were showing in the marketplace as measurements 20-22.
"If buyers measuring 20-22 acquire them they will likely be quite upset," she explained.
A different user, from Derby, said she had been left angered by the change as she had to manually change the sizing for "all her products".
"For me this is particularly frustrating, since I have chronic health issues and Vinted sales have been crucial after experiencing income reduction," she stated.
The service features exceeding 100 million members, with 18 million British users.
It has proved a popular alternative compared to resale services such as eBay and Depop.
This represents another occasion that an unexpected update within the service has received backlash: earlier, the service retracted a modification to its shipping options due to shopper criticism.
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