Hi and welcome to the site, imanbahrani :)
The data that comes up in the research lab is based on the actual number of listings on eBay. I don't think there is a bug. It might just happen that based on the total number of listings the item you searched for has very low competition.
I tried the keyword 'antiques' and got this result for competition -
eBay US Very High
eBay UK Low
eBay Canada Very High
eBay Australia Very Low
You might find this helpful -
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Cheers!