bash script curl upload files to php page

Question

I am not sure that I am posting on the correct forum. I am working with Linux Centos 7 and I write a bash script which take all files with txt extension from a directory to upload them to the server with php. The bash script seems to find all files inside the directory but it upload only one file and at the end of the process my php page is deleted.

My bash script:

#!/bin/sh
for filename in $(find /home/rico/mywebsite/ -maxdepth 1 -name \*.txt )
do
echo ${filename}
curl -O -X POST -F 'avatar=@'${filename} http://localhost/ions/uploadTXT.php
done;

and my php page is written like that:

<?php
error_reporting(E_ALL); ini_set('display_errors', 1);

$dir = '/opt/lampp/htdocs/ions/upload/';
$filename = basename($_FILES['avatar']['name']); //this var is for the parameter past into input field and used for $handle

if(move_uploaded_file($_FILES['avatar']['tmp_name'], $dir . $filename)) {
}
?>