json code not work

[M-Shahroz]

Warning: Undefined array key 1 in C:\xampp\htdocs\TikGet-main\tikget.class.php on line 70

Warning: Undefined array key 1 in C:\xampp\htdocs\TikGet-main\tikget.class.php on line 70
NULL and this code is not working and give me errors if(strpos($resp, $this->patterns[0]) !== false){ $tiktokUrl = explode($this->patterns[1],explode($this->patterns[0],$resp)[1])[0]; $resp = $this->curlTikTok($tiktokUrl); }

    $json = explode($this->patterns[2],explode($this->patterns[3],explode($this->patterns[4],$resp)[1])[0])[1];
 
    $json = json_decode($json);
    if($json == null){
        return false;
    }   plz solve this issue i am working on this api