update response body

Author: aracho1

mobile-save-for-later/src/main/scala/com/gu/sfl/controller/SaveArticlesController.scala

@@ -5,7 +5,7 @@ import com.gu.sfl.exception.{IdentityServiceError, MissingAccessTokenError, Okta
 import com.gu.sfl.lambda.{LambdaRequest, LambdaResponse}
 import com.gu.sfl.lib.Base64Utils
 import com.gu.sfl.lib.Jackson._
-import com.gu.sfl.model.{DirtySavedArticles, SavedArticles}
+import com.gu.sfl.model.{DirtySavedArticles, Error, SavedArticles}
 import com.gu.sfl.savedarticles.UpdateSavedArticles
 import com.gu.sfl.util.StatusCodes
 
@@ -26,7 +26,7 @@ class SaveArticlesController(updateSavedArticles: UpdateSavedArticles)(implicit
           case Failure(t) => {
             val headersWithoutAuth = lambdaRequest.headers.filter{ case (k,v) => headersToKeep.contains(k.toLowerCase)}
             logger.warn(s"Could not read value: $json \nWith headers: $headersWithoutAuth" )
-            Future { LambdaResponse(StatusCodes.badRequest, Some("Could not parse request body")) }
+            Future { lambdaErrorResponse(StatusCodes.badRequest, List(Error("Bad Request", "Could not parse request body"))) }
           }
           case _ => futureSave(triedSavedArticles, lambdaRequest.headers)
         }