diff --git a/changelog.d/5-internal/WPB-11386-map-range b/changelog.d/5-internal/WPB-11386-map-range
new file mode 100644
index 00000000000..a01f45001c9
--- /dev/null
+++ b/changelog.d/5-internal/WPB-11386-map-range
@@ -0,0 +1 @@
+Introduce length-preserving function mapRange to replace Functor instance for Range data type.
\ No newline at end of file
diff --git a/libs/types-common/src/Data/Range.hs b/libs/types-common/src/Data/Range.hs
index 73cdda9fea7..c4401541756 100644
--- a/libs/types-common/src/Data/Range.hs
+++ b/libs/types-common/src/Data/Range.hs
@@ -26,6 +26,7 @@
 module Data.Range
   ( Range,
     toRange,
+    mapRange,
     Within,
     Bounds (..),
     checked,
@@ -98,7 +99,10 @@ import Test.QuickCheck qualified as QC
 newtype Range (n :: Nat) (m :: Nat) a = Range
   { fromRange :: a
   }
-  deriving (Eq, Ord, Show, Functor)
+  deriving (Eq, Ord, Show)
+
+mapRange :: forall (n :: Nat) (m :: Nat) a b. (a -> b) -> Range n m [a] -> Range n m [b]
+mapRange f (Range as) = Range (f `map` as)
 
 toRange :: (n <= x, x <= m, KnownNat x, Num a) => Proxy x -> Range n m a
 toRange = Range . fromIntegral . natVal
diff --git a/services/brig/src/Brig/IO/Intra.hs b/services/brig/src/Brig/IO/Intra.hs
index d4eef4df895..39f2250eea1 100644
--- a/services/brig/src/Brig/IO/Intra.hs
+++ b/services/brig/src/Brig/IO/Intra.hs
@@ -326,7 +326,7 @@ notifyUserDeletionRemotes deleted = do
           pure ()
         Just rangedUcs -> do
           luidDeleted <- qualifyLocal' deleted
-          embed $ notifyUserDeleted luidDeleted (qualifyAs ucs ((fmap (fmap (qUnqualified . ucTo))) rangedUcs))
+          embed $ notifyUserDeleted luidDeleted (qualifyAs ucs (mapRange (qUnqualified . ucTo) rangedUcs))
           -- also sent connection cancelled events to the connections that are pending
           let remotePendingConnections = qualifyAs ucs <$> filter ((==) Sent . ucStatus) (fromRange rangedUcs)
           forM_ remotePendingConnections $ sendCancelledEvent luidDeleted