diff --git a/build/deploy-netlify.mjs b/build/deploy-netlify.mjs
index 8431162a..296d3ed8 100644
--- a/build/deploy-netlify.mjs
+++ b/build/deploy-netlify.mjs
@@ -36,7 +36,7 @@ const MAX_RETRIES = 5;
     }
 
     if (config.branch === 'main') {
-        config.branch = null;
+        config.branch = undefined;
     }
 
     const files = await listFilesWithHashes(config.rootFolder, config.exclude, 'sha1');