diff --git a/src/main/java/com/googlesource/gerrit/plugins/lfs/locks/LfsLocksHandler.java b/src/main/java/com/googlesource/gerrit/plugins/lfs/locks/LfsLocksHandler.java
index 1de28f4..c4a1ad3 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/lfs/locks/LfsLocksHandler.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/lfs/locks/LfsLocksHandler.java
@@ -99,7 +99,8 @@
     }
 
     LfsLock lock = hasLock.get();
-    if (lock.owner.name.equals(user.getUserName().get())) {
+    Optional<String> username = user.getUserName();
+    if (username.isPresent() && lock.owner.name.equals(username.get())) {
       locks.deleteLock(lock);
       return new LfsLockResponse(lock);
     } else if (input.force) {