diff --git a/lib/util/git/index.ts b/lib/util/git/index.ts
index 107c67decd1241..ec518a307f6384 100644
--- a/lib/util/git/index.ts
+++ b/lib/util/git/index.ts
@@ -781,6 +781,7 @@ export async function mergeBranch(
   let status: StatusResult | undefined;
   try {
     await syncGit();
+    await writeGitAuthor();
     await git.reset(ResetMode.HARD);
     await gitRetry(() =>
       git.checkout(['-B', branchName, 'origin/' + branchName])