How to report allocable loss from 401K excess contribution?

I have a 1099-R for excess 401K contribution made in 2022 and I already reported $2500 as other earned income on 2022 tax return. When I got the refund check, it listed as follows,
Excess contributions: $2500
(Allocable Loss) : ($500)
Amount of Refund: $2000
Now 1099-R form only has the Gross distribution of $2000 and doesn't have $500 loss.

My question is how to repot the loss of $500? If I don't, I have paid taxes for $2500 but in fact I should only pay taxes for $2000.

Thank you for your help!