diff --git a/runtime/lua/vim/lsp/handlers.lua b/runtime/lua/vim/lsp/handlers.lua
index ebf504fd42..22089aaaa6 100644
--- a/runtime/lua/vim/lsp/handlers.lua
+++ b/runtime/lua/vim/lsp/handlers.lua
@@ -28,7 +28,7 @@ local function progress_handler(_, result, ctx, _)
   local client_name = client and client.name or string.format("id=%d", client_id)
   if not client then
     err_message("LSP[", client_name, "] client has shut down after sending the message")
-    return
+    return vim.NIL
   end
   local val = result.value    -- unspecified yet
   local token = result.token  -- string or number
@@ -70,7 +70,7 @@ M['window/workDoneProgress/create'] =  function(_, result, ctx)
   local client_name = client and client.name or string.format("id=%d", client_id)
   if not client then
     err_message("LSP[", client_name, "] client has shut down after sending the message")
-    return
+    return vim.NIL
   end
   client.messages.progress[token] = {}
   return vim.NIL