A glitch in the mail sending script, sends 200 times to everyone in a row, why?

Question

PHP

hello, please tell me, they redid the script for a newer version of php and added phpmailer, as a result, now letters are sent to all users in a row and 200 pieces each, can someone look at the script and tell me where the error is so that I can fix it, I don’t understand why .
As far as I know, there are 2 files that are responsible for sending
mails.php
and pereodic.php
pereodic.php
here are the old files that worked without phpmailer and on the old version of php
mails.php
mails.php
pereodic.php
who understands sending mail via php please help me find the problem