The data i get back to FETCH from my PHP file, had an added empty paragraph at the beginning - fetch-api

Question

I use the FETCH API to pull data from the backend, but since some time I am getting an empty paragraph at the beginning of each response. Unfortunately for me, I am not able to track down what change was made that has caused this, so I am looking for possible reasons why this would happen in order to eliminate it.
Below is once such fetch:
await fetch('__transport.php', {
method: "POST",
body: new URLSearchParams("pk="+pk+"&drvr="+drvr+"&col="+col)
})
.then(response => response.text())
.then((response) => {
if(response.substr(0,6) == "Failed") {
alert(response)
} else {
document.getElementById(id).innerHTML = response;
}
})
.catch(err => console.log('s/g went wrong', err));
and here the backend, the mysql query was removed from the end, but it returns a name
$pk = $_POST['pk'];
$drvr = ($_POST['drvr'] != 0 ? $_POST['drvr']:'NULL');
$col = $_POST['col'];
$sql = "UPDATE mytable
SET
$col = $drvr
WHERE pkcolumn = $pk";
if ($conn->Execute($sql)==false) {
exit("Failed to update database\n\n".$conn->ErrorMsg()."\n\n".$sql);
} else if($drvr != 'NULL'){
//mysql query removed for simplification as I get the same result with this
$name = "Jack Sparrow";
exit($name); //returns the name to the above FETCH
} else {
exit(' '); //returns no name as the field should be blank in this case
}
I am expecting the return "Jack Sparrow" to be received by the JavaScript in the variable "response", as:
"Jack Sparrow"
What I get is and empty paragraph followed by the name:
"
Jack Sparrow"