diff --git a/src/libcharon/sa/ikev2/tasks/child_create.c b/src/libcharon/sa/ikev2/tasks/child_create.c
index 5a6c1b431..399aa1f81 100644
--- a/src/libcharon/sa/ikev2/tasks/child_create.c
+++ b/src/libcharon/sa/ikev2/tasks/child_create.c
@@ -1094,8 +1094,7 @@ METHOD(task_t, build_i, status_t,
 		case CREATE_CHILD_SA:
 			if (!generate_nonce(this))
 			{
-				message->add_notify(message, FALSE, NO_PROPOSAL_CHOSEN,
-									chunk_empty);
+				message->set_exchange_type(message, EXCHANGE_TYPE_UNDEFINED);
 				return SUCCESS;
 			}
 			if (!this->retry && this->dh_group == MODP_NONE)