Keep leading zeros in CSV file through PHP - php

Question

I have a problem. I’ve created a web form in HTML that stores data from inputs in CSV file through PHP file using fputcvs function.
Now... When I open that CSV file in Excel, or via =IMPORTDATA function in google sheets, it deletes leading zeros (0). The leading zeros are very important in my case.
Any way or trick to fix it through the PHP or HTML file?
Thanks
My PHP code:
<?php
$fieldA = $_POST["prezime"];
$fieldB = $_POST["ime"];
$fieldC = $_POST["datumrodjenja"];
$fieldD = $_POST["mestorodjenja"];
$fieldE = $_POST["rod"];
$fieldF = $_POST["prebivaliste"];
$fieldG = $_POST["brojpasosa"];
$fieldH = $_POST["izdatod"];
$fieldI = $_POST["vazido"];
$fieldJ = $_POST["profesija"];
$fieldK = $_POST["zanimanje"];
$fieldL = $_POST["fiksni"];
$fieldM = $_POST["mobilni"];
$fieldN = $_POST["email"];
$fieldO = $_POST["napomena"];
$keys = array($fieldA,$fieldB,$fieldC,$fieldD,$fieldE,$fieldF,$fieldG,$fieldH,$fieldI,$fieldJ,$fieldK,$fieldL,$fieldM,$fieldN,$fieldO); //THIS IS WHERE YOU PUT THE FORM ELEMENTS ex: array('$fieldA','$fieldB',etc)
$keys = ["prezime", "ime", "datumrodjenja", "mestorodjenja", "rod", "prebivaliste",
"brojpasosa", "izdatod", "vazido", "profesija", "zanimanje", "fiksni", "mobilni",
"email", "napomena"];
$labels = ["Prezime", "Ime", "Datum Rođenja", "Mesto Rođenja", "Rod", "Prebivalište",
"Broj Pasoša", "Izdat Od", "Važi Do", "Profesija", "Trenutno Zanimanje", "Tel. Fiksni", "Tel. Mobilni",
"E-mail Adresa", "Napomena"];
$values = [];
foreach ($keys as $key)
$values[] = $_POST[$key];
$fname = 'prijave.csv';
if (!file_exists($fname)) {
$fp = fopen($fname,'a');
//add BOM to fix UTF-8 in Excel
fputs($fp, $bom =( chr(0xEF) . chr(0xBB) . chr(0xBF) ));
fputcsv($fp, $labels);
}
else {
$fp = fopen($fname,'a');
}
fputcsv($fp, $values);
fclose($fp);