"Units sold past month" Metric Not being shown anymore on Search Results

Hey guys,

I have encountered a new problem yet again where the "[no.] of units sold past month" metric is no longer being shown to customers on the search results and Detail Page of affected ASINs, whereas all of my competitors in the niche do show this metric! This has drastically reduced my sales.

Seller support is clueless and unhelpful. Anyone know about this?