Vinted users have been reacting angrily following a change that caused products showing incorrect sizing.
The second-hand shopping app has altered its sizing categories for women's and children's clothes without notifying all users about the change.
Countless users and merchants have taken to social media claiming that product pages now present a different size category than originally posted due to the recalibration.
Vinted explained the updated approach better aligns with similar services.
They have suggested members to check their listings and manually change the size where appropriate, resulting in member annoyance.
Earlier, the measurements included a single numeric size and a letter, like S/8 or M/10.
The new system has a letter with a size spectrum for example S/UK 8-10.
For certain items, the sizing has been recategorised - such as a large size was previously a 12 but currently displays as UK 16-18.
Frankie Bridger, who creates plus-size fashion videos, said the change "makes both selling and buying harder".
"Few clothing companies classify XL as 20-22," as the platform currently indicates.
Stephanie Gallen, from Glasgow, stated items she posted on Vinted with size 14 labels were showing in the marketplace as size 20–22.
"Should someone sized 20-22 purchase these they will likely be quite upset," she stated.
A different user, from Derby, said she had been left angered due to the update requiring manual adjustment the sizing for "all her products".
"This situation is especially annoying, because of my ongoing medical condition and platform income has been essential for me since losing part of my income," she said.
The service features exceeding 100 million users, comprising 18 million UK members.
It has emerged as a preferred choice compared to resale services such as eBay and Depop.
This represents another occasion where an unanticipated change within the service has received backlash: earlier, Vinted reversed a change concerning shipment methods following member complaints.
Dr. Elara Voss is a tech analyst and futurist with a Ph.D. in Computer Science, specializing in emerging technologies and their societal impact.