Data from separate function being merged in excel - php

Question

Im working on 2 json data which I need to transfer the data to separate excel files. What I did is, I made 2 function so that I can choose what file to be downloaded. The problem is when I tried to call both, the data is merged on a single excel. What I expect is it will be downloaded separately.
I tried adding sleep after the first function but didn't work, still the same output. I tried also using die after both function but only the first one is working.
Hope you help me.
SAMPLE CODE
function.php
<?php
function bjpk(){
$json = 'api link...';
$arr = json_decode(file_get_contents($json), true);
$name = $arr['code'];
header("Content-Disposition: attachment; filename=\"$name.xls\"");
header("Content-Type: application/vnd.ms-excel;");
header("Pragma: no-cache");
header("Expires: 0");
$out = fopen("php://output", 'w');
$data = array();
foreach ($arr['data'] as $key => $value) {
$data['date'] = substr($value['opentime'], 0, -9);
$data['num'] = substr($value['expect'], 4);
$codes = explode(',', $value['opencode']);
foreach ($codes as $key => $code) {
$data[$key] = $code;
}
fputcsv($out, $data,"\t");
}
fclose($out);
}
function cqssc(){
$json = 'api link..';
$arr = json_decode(file_get_contents($json), true);
$name = $arr['code'];
header("Content-Disposition: attachment; filename=\"$name.xls\"");
header("Content-Type: application/vnd.ms-excel;");
header("Pragma: no-cache");
header("Expires: 0");
$out = fopen("php://output", 'w');
$data = array();
foreach ($arr['data'] as $key => $value) {
$date = DateTime::createFromFormat('Ymd', substr($value['expect'], 0, -3));
$data['date'] = $date->format('Y-m-d');
$data['num'] = substr($value['expect'], 8);
$codes = explode(',', $value['opencode']);
foreach ($codes as $key => $code) {
$data[$key] = $code;
}
fputcsv($out, $data,"\t");
}
fclose($out);
}
index.php
<?php
require_once ('function.php');
bjpk();
cqssc();