Grid return 2 data instead of 1 data,

Hi, i often found this bug, but this is makes me confused

so, in my screenshot. there is 2 same data, that if i click one of them, it select 2 data (but actually it just one data). whats wrong with my program? (in this case, only this data is doubled)

for search component im using Specification. i’ll provide my code if you asked. thank you !
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