diff --git a/hls-floskell-plugin.cabal b/hls-floskell-plugin.cabal
--- a/hls-floskell-plugin.cabal
+++ b/hls-floskell-plugin.cabal
@@ -1,6 +1,6 @@
 cabal-version:      2.4
 name:               hls-floskell-plugin
-version:            2.0.0.1
+version:            2.1.0.0
 synopsis:           Integration with the Floskell code formatter
 description:
   Please see the README on GitHub at <https://github.com/haskell/haskell-language-server#readme>
@@ -28,9 +28,10 @@
   build-depends:
     , base            >=4.12 && <5
     , floskell        ^>=0.10
-    , ghcide          == 2.0.0.1
-    , hls-plugin-api  == 2.0.0.1
-    , lsp-types       ^>=1.6
+    , ghcide          == 2.1.0.0
+    , hls-plugin-api  == 2.1.0.0
+    , lsp-types       ^>=2.0.1.0
+    , mtl
     , text
     , transformers
 
@@ -48,4 +49,4 @@
     , base
     , filepath
     , hls-floskell-plugin
-    , hls-test-utils       == 2.0.0.1
+    , hls-test-utils       == 2.1.0.0
diff --git a/src/Ide/Plugin/Floskell.hs b/src/Ide/Plugin/Floskell.hs
--- a/src/Ide/Plugin/Floskell.hs
+++ b/src/Ide/Plugin/Floskell.hs
@@ -5,15 +5,17 @@
   , provider
   ) where
 
+import           Control.Monad.Except        (throwError)
 import           Control.Monad.IO.Class
-import qualified Data.Text               as T
-import qualified Data.Text.Lazy          as TL
-import qualified Data.Text.Lazy.Encoding as TL
-import           Development.IDE         hiding (pluginHandlers)
+import qualified Data.Text                   as T
+import qualified Data.Text.Lazy              as TL
+import qualified Data.Text.Lazy.Encoding     as TL
+import           Development.IDE             hiding (pluginHandlers)
 import           Floskell
+import           Ide.Plugin.Error
 import           Ide.PluginUtils
 import           Ide.Types
-import           Language.LSP.Types
+import           Language.LSP.Protocol.Types
 
 -- ---------------------------------------------------------------------
 
@@ -28,16 +30,16 @@
 -- Formats the given source in either a given Range or the whole Document.
 -- If the provider fails an error is returned that can be displayed to the user.
 provider :: FormattingHandler IdeState
-provider _ideState typ contents fp _ = liftIO $ do
+provider _ideState typ contents fp _ = do
     let file = fromNormalizedFilePath fp
-    config <- findConfigOrDefault file
+    config <- liftIO $ findConfigOrDefault file
     let (range, selectedContents) = case typ of
           FormatText    -> (fullRange contents, contents)
-          FormatRange r -> (normalize r, extractRange r contents)
+          FormatRange r -> (normalize r, extractTextInRange (extendToFullLines r) contents)
         result = reformat config (Just file) . TL.encodeUtf8 $ TL.fromStrict selectedContents
     case result of
-      Left  err -> pure $ Left $ responseError $ T.pack $ "floskellCmd: " ++ err
-      Right new -> pure $ Right $ List [TextEdit range . TL.toStrict $ TL.decodeUtf8 new]
+      Left  err -> throwError $ PluginInternalError $ T.pack $ "floskellCmd: " ++ err
+      Right new -> pure $ InL [TextEdit range . TL.toStrict $ TL.decodeUtf8 new]
 
 -- | Find Floskell Config, user and system wide or provides a default style.
 -- Every directory of the filepath will be searched to find a user configuration.