diff --git a/src/reporters/compact.ts b/src/reporters/compact.ts
index 4702b65f4..e1f5b2acf 100644
--- a/src/reporters/compact.ts
+++ b/src/reporters/compact.ts
@@ -18,7 +18,7 @@ export default ({ report, issues, isShowProgress }: ReporterOptions) => {
       const issuesForType = isSet
         ? Array.from(issues[reportType] as IssueSet)
         : reportType === 'duplicates'
-        ? Object.values(issues[reportType]).map(Object.values).flat()
+        ? Object.values(issues[reportType]).flatMap(Object.values)
         : Object.values(issues[reportType] as IssueRecords).map(issues => {
             const items = Object.values(issues);
             return { ...items[0], symbols: items.map(issue => issue.symbol) };
diff --git a/src/reporters/json.ts b/src/reporters/json.ts
index a6cf86531..2b6cf6d31 100644
--- a/src/reporters/json.ts
+++ b/src/reporters/json.ts
@@ -40,7 +40,7 @@ export default async ({ report, issues, options }: ReporterOptions) => {
   const codeownersFilePath = resolve(opts.codeowners ?? '.github/CODEOWNERS');
   const codeownersEngine = isFile(codeownersFilePath) && OwnershipEngine.FromCodeownersFile(codeownersFilePath);
 
-  const flatten = (issues: IssueRecords): Issue[] => Object.values(issues).map(Object.values).flat();
+  const flatten = (issues: IssueRecords): Issue[] => Object.values(issues).flatMap(Object.values);
 
   const initRow = (filePath: string) => {
     const file = relative(filePath);