i have database with this tables
users 
  user_id 
  user_name 
  user_email
  user_password 
  user_reg_date 
and i have second table user_tokens
user_tokens 
  token_id 
  token_user_id
  token_user_agent 
  toke_hash 
  token_created 
  token_expires 
foreighn key token_user_id is references to user_id
php code here
    $sql = 'INSERT INTO user_tokens 
            (token_user_id, token_user_agent, token_hash, token_created, token_expires) 
            VALUES (:userid, :uagent, :thash, :tcurrent, :texpires)';
            $ua = serialize($visitor->get_userspecs());
            $time = intval(time());
            $binder = array(
                ':userid'           => $userid,
                ':uagent'           => serialize($visitor->get_userspecs()),
                ':thash'            => $userhash,
                ':tcurrent'         => time(),
                ':texpires'         => strtotime('+2 Days')
            );
            $this->preAction($sql, $binder);
            if(!$this->doAction()) {
                return null;
            }
php request is using PDO
    $this->stmt = $this
                ->get_con()
                ->prepare($this->sql);
            if (!$this->stmt) 
                throw new RuntimeException('SQL preparing failure! '.$stmt->errorCode());
            if (!empty($this->prepared)) {
                foreach ($this->prepared as $key => $value) {
                    $this->stmt->bindParam($key, $value);
                }
            } 
            $check = $this->stmt->execute();
i as i know when i printing $binder -> via print_r $user_id shows 4 this is same as in users -> user_id i got
when i try execute sql i got error
SQLSTATE[23000]: Integrity constraint violation: 1452 Cannot add or update a child row: a foreign key constraint fails (`modulecms`.`user_tokens`, CONSTRAINT `user_tokens_ibfk_1` FOREIGN KEY (`token_user_id`) REFERENCES `users` (`user_id`))
in log i got this
  2020-01-06T18:50:47.015764Z      26 Prepare   SELECT token_hash as token 
                FROM user_tokens WHERE token_user_id = ? LIMIT 1
2020-01-06T18:50:47.015803Z    26 Close stmt    
2020-01-06T18:50:47.015826Z    26 Execute   SELECT token_hash as token 
                FROM user_tokens WHERE token_user_id = '4' LIMIT 1
2020-01-06T18:50:47.015987Z    26 Close stmt    
2020-01-06T18:50:47.016396Z    26 Prepare   INSERT INTO user_tokens 
            (token_user_id, token_user_agent, token_hash, token_created, token_expires) 
            VALUES (?, ?, ?, ?, ?)
2020-01-06T18:50:47.016467Z    26 Execute   INSERT INTO user_tokens 
            (token_user_id, token_user_agent, token_hash, token_created, token_expires) 
            VALUES ('1578509447', '1578509447', '1578509447', '1578509447', '1578509447')
2020-01-06T18:50:47.017541Z    26 Close stmt
what's my problem? why i have this all placeholders re-writed by timestamp?
 
    