diff --git a/lib/util/git/index.ts b/lib/util/git/index.ts
index 7c9f5512eba8e8ad6e9c0e687cc61002c9ac4950..2b3df1332622483ad6e52e89ebd8237984b1386c 100644
--- a/lib/util/git/index.ts
+++ b/lib/util/git/index.ts
@@ -261,7 +261,12 @@ export function setGitAuthor(gitAuthor: string): void {
 }
 
 export async function writeGitAuthor(): Promise<void> {
-  const { gitAuthorName, gitAuthorEmail } = config;
+  const { gitAuthorName, gitAuthorEmail, writeGitDone } = config;
+  // istanbul ignore if
+  if (writeGitDone) {
+    return;
+  }
+  config.writeGitDone = true;
   try {
     if (gitAuthorName) {
       logger.debug({ gitAuthorName }, 'Setting git author name');
@@ -579,7 +584,7 @@ export async function isBranchConflicted(
 ): Promise<boolean> {
   logger.debug(`isBranchConflicted(${baseBranch}, ${branch})`);
   await syncGit();
-
+  await writeGitAuthor();
   if (!branchExists(baseBranch) || !branchExists(branch)) {
     logger.warn(
       { baseBranch, branch },
diff --git a/lib/util/git/types.ts b/lib/util/git/types.ts
index b716298087045f361b427246ae9a6b0b77879efd..f7027b8f837385c77e180856bb217b593de8a806 100644
--- a/lib/util/git/types.ts
+++ b/lib/util/git/types.ts
@@ -28,6 +28,8 @@ export interface LocalConfig extends StorageConfig {
   ignoredAuthors: string[];
   gitAuthorName?: string;
   gitAuthorEmail?: string;
+
+  writeGitDone?: boolean;
 }
 
 export interface FileAddition {