diff --git a/apps/web/Controllers/API/AuctionsController.cs b/apps/web/Controllers/API/AuctionsController.cs
index 84ff4e8c7..9069d0b55 100644
--- a/apps/web/Controllers/API/AuctionsController.cs
+++ b/apps/web/Controllers/API/AuctionsController.cs
@@ -331,9 +331,15 @@ public async Task<IActionResult> Missing([FromBody] ApiMissingAuctionsForm form)
                     !accountPetIds.Contains(pet.Id))
                 .ToArrayAsync();
 
-            var petItemMap = missingPets
-                .Where(pet => pet.ItemIds.Count > 0)
-                .ToManyDictionary(pet => pet.ItemIds, pet => pet.CreatureId);
+            // ItemId -> CreatureId
+            var petItemMap = new Dictionary<int, int>();
+            foreach (var missingPet in missingPets.Where(pet => pet.ItemIds.Count > 0))
+            {
+                foreach (int itemId in missingPet.ItemIds)
+                {
+                    petItemMap.TryAdd(itemId, missingPet.CreatureId);
+                }
+            }
 
             var petSpeciesMap = missingPets
                 .ToDictionary(pet => pet.Id, pet => pet.CreatureId);