diff --git a/src/jaxsim/api/data.py b/src/jaxsim/api/data.py
index b880547b9..bedd6009b 100644
--- a/src/jaxsim/api/data.py
+++ b/src/jaxsim/api/data.py
@@ -230,7 +230,7 @@ def build(
                 )
 
             else:
-                contacts_params = model.contact_model._parameters_class()
+                contacts_params = model.contact_model()._parameters_class()
 
         return JaxSimModelData(
             state=ode_state,