User profile linking can get stuck with null profile_id after partial observer failure

app/Observers/UserObserver.php

@@ -61,11 +61,24 @@ class UserObserver
             return;
         }
 
-        if (Profile::whereUsername($user->username)->exists()) {
-            return;
-        }
-
         if (empty($user->profile)) {
+            // Check if an orphaned profile exists (created but never linked)
+            $existingProfile = Profile::whereUsername($user->username)->first();
+
+            if ($existingProfile) {
+                // Link orphaned profile to user if profile_id is not set
+                if (! $user->profile_id) {
+                    DB::transaction(function () use ($user, $existingProfile) {
+                        $user = User::findOrFail($user->id);
+                        $user->profile_id = $existingProfile->id;
+                        $user->save();
+                    });
+                }
+
+                return;
+            }
+
+            // Create profile and link to user in a single atomic transaction
             $profile = DB::transaction(function () use ($user) {
                 $profile = new Profile;
                 $profile->user_id = $user->id;
@@ -86,22 +99,15 @@ class UserObserver
                 $profile->save();
                 $this->applyDefaultDomainBlocks($user);
 
-                return $profile;
-            });
-
-            DB::transaction(function () use ($user, $profile) {
                 $user = User::findOrFail($user->id);
                 $user->profile_id = $profile->id;
                 $user->save();
 
-                // UserNotify::updateOrCreate([
-                //     'profile_id' => $profile->id,
-                //     'user_id' => $user->id,
-                // ]);
-
-                CreateAvatar::dispatch($profile);
+                return $profile;
             });
 
+            CreateAvatar::dispatch($profile);
+
             if ((bool) config_cache('account.autofollow') == true) {
                 $names = config_cache('account.autofollow_usernames');
                 $names = explode(',', $names);