Looping through PHP array shows invalid Response - php

Question

I have created a function in PHP that mainly index files from a txt file here is the function that was supposed to do the job
public function getPlayingItem()
{
$playData = [];
$startTimes = [];
for($i=0; $i < count($this->playListFiles); $i++){
$item = $this->playListFiles[$i];
if(empty($item)){
unset($this->playListFiles[$i]);
continue;
}
$tmp = explode(',', $item);
$playData[$i]['startTime'] = array_pop($tmp);
$startTimes[$i] = $playData[$i]['startTime'];
$playData[$i]['name'] = implode(',',$tmp);
}
array_multisort($startTimes, SORT_ASC, $playData);
for($i=0; $i < count($playData); $i++){
if (strtotime($playData[$i]['startTime']) >= time()){
break;
}
}
$info = $this->get_mp3($playData[$i-1]['name'], true, false);
$tmp = explode(DS,$playData[$i-1]['name']);
$name = array_pop($tmp);
$playing = ['number'=>($i-1),'path'=>$playData[$i-1]['name'],'name'=>$name,'duration'=>$info['data']['time'],'startTime'=>$playData[$i-1]['startTime']];
$info = $this->get_mp3($playData[$i]['name'], true, false);
$tmp = explode(DS,$playData[$i]['name']);
$name = array_pop($tmp);
$next = ['number'=>$i,'path'=>$playData[$i]['name'],'name'=>$name,'duration'=>$info['data']['time'],'startTime'=>$playData[$i]['startTime']];
$output = ['playing'=>$playing, 'next'=>$next];
return $output;
}
Here is the txt file
E:\xampp\htdocs\radioclass\files\2021-02-23 22.47.04.mp3,19:10:00
E:\xampp\htdocs\radioclass\files\2021-03-15 19.39.25.mp3,19:10:39
E:\xampp\htdocs\radioclass\files\2021-05-15 19.05.13.mp3,19:10:43
E:\xampp\htdocs\radioclass\files\2021-07-14 23.04.50.mp3,19:11:03
E:\xampp\htdocs\radioclass\files\2021-08-31 11.55.38.mp3,19:11:05
E:\xampp\htdocs\radioclass\files\2021-08-31 11.56.23.mp3,19:11:09
E:\xampp\htdocs\radioclass\files\2021-09-03 23.47.38#ssr.mp3,19:12:19
E:\xampp\htdocs\radioclass\files\frmu.mp3,19:12:23
E:\xampp\htdocs\radioclass\files\frmun.mp3,19:12:26
The response:
{"playing":{"number":8,"path":"E:\\xampp\\htdocs\\radioclass\\files\\frmun.mp3","name":"frmun.mp3","duration":"00:10","startTime":"19:12:26"},"next":{"number":9,"path":null,"name":"","duration":null,"startTime":null}}
**Now the problem is that first of all it should start from 0 and end at 10 and the second thing is that it shows the path, name, duration, of the second line as null any help will be greatly appreciated because I'm a begginer **