Transaction rollback function not work in Codeigniter - php

Question

when i run this code data insert in 3 tables successfully and commit when in give the error in in 3rd table insert query then data insert in 1st and 2nd table and not in 3rd table and also not RollBack function work properly. I want do when 3rd table query not work then 1st and 2nd table insert data will remove and delete.
$this->db->trans_start(TRUE);
// 1st table insert query
$this->db->insert('users',$userInfo);
$userId = $this->db->insert_id();
$query = $this->db->query("SELECT `roleId` FROM `role` WHERE roleName='Clint';");
foreach ($query->result_array() as $row)
{ $roleId = $row['roleId']; }
$user_role = array( 'user_id' => $userId, 'role_id' => $roleId );
// 2nd table insert query
$this->db->insert('user_role', $user_role);
$city_id += [ "projectInfo" => $userId ];
// 3rd table insert query
$this->db->insert('project', $projectInfo);
$this->db->trans_complete();
if ($this->db->trans_status() === FALSE )
{
echo "Flase";
$this->db->trans_rollback();
}
else
{
echo "True";
$this->db->trans_rollback();
}

Answer 1

You are manually rolling back transactions! In this case, you should use
$this->db->trans_begin(); NOT $this->db->trans_start();
CI automatically rolls back transactions, you dont need do it manually.
If you use $this->db->trans_start, you dont need $this->db->trans_rollback().
Comment out $this->db->trans_rollback(), or leave those and use $this->db->trans_begin(), then check results.
https://www.codeigniter.com/user_guide/database/transactions.html
Good luck!