diff --git a/lib/towerops/snmp.ex b/lib/towerops/snmp.ex
index 401e0c74..c7ab33d8 100644
--- a/lib/towerops/snmp.ex
+++ b/lib/towerops/snmp.ex
@@ -1570,6 +1570,8 @@ defmodule Towerops.Snmp do
   def upsert_mac_address(attrs) do
     import Ecto.Query
 
+    require Logger
+
     # Build query to find existing MAC address entry
     query =
       from m in MacAddress,
@@ -1583,16 +1585,36 @@ defmodule Towerops.Snmp do
         vlan_id -> where(query, [m], m.vlan_id == ^vlan_id)
       end
 
-    case Repo.one(query) do
-      nil ->
+    # Use Repo.all to handle potential duplicates gracefully
+    # If duplicates exist, keep the first one and delete the rest
+    case Repo.all(query) do
+      [] ->
         %MacAddress{}
         |> MacAddress.changeset(attrs)
         |> Repo.insert()
 
-      mac_address ->
+      [mac_address] ->
         mac_address
         |> MacAddress.changeset(attrs)
         |> Repo.update()
+
+      [first | duplicates] ->
+        # Handle duplicates: delete extras, update first
+        Logger.warning("Found #{length(duplicates)} duplicate MAC address entries, cleaning up",
+          device_id: attrs.device_id,
+          mac_address: attrs.mac_address,
+          vlan_id: attrs[:vlan_id],
+          duplicate_ids: Enum.map(duplicates, & &1.id)
+        )
+
+        # Delete duplicate entries
+        duplicate_ids = Enum.map(duplicates, & &1.id)
+        Repo.delete_all(from m in MacAddress, where: m.id in ^duplicate_ids)
+
+        # Update the remaining entry
+        first
+        |> MacAddress.changeset(attrs)
+        |> Repo.update()
     end
   end