diff --git a/api/app/Models/Workspace.php b/api/app/Models/Workspace.php
index acdc1463..b200f7ff 100644
--- a/api/app/Models/Workspace.php
+++ b/api/app/Models/Workspace.php
@@ -204,11 +204,11 @@ public function forms()
         return $this->hasMany(Form::class);
     }
 
-    public function isReadonlyUser(User $user)
+    public function isReadonlyUser(?User $user)
     {
-        return $this->users()
+        return $user ? $this->users()
             ->wherePivot('user_id', $user->id)
             ->wherePivot('role', User::ROLE_READONLY)
-            ->exists();
+            ->exists() : false;
     }
 }