diff --git a/app/Console/Commands/MiningTaxes/MiningTaxesObservers.php b/app/Console/Commands/MiningTaxes/MiningTaxesObservers.php
index 29eb272b7..db9b0fdc1 100644
--- a/app/Console/Commands/MiningTaxes/MiningTaxesObservers.php
+++ b/app/Console/Commands/MiningTaxes/MiningTaxesObservers.php
@@ -105,7 +105,7 @@ class MiningTaxesObservers extends Command
          * Cleanup stale data that hasn't been updated in at least 1 week.
          */
         $date = Carbon::now()->subDay(7);
-        Observer::where('updated_at', '<', $date)->delete();
+        Observer::where('last_updated', '<', $date)->delete();