Execution time exceeded PHP Carbon - php

Question

I have this function which checks the start, end and repeat date. So start and end dates serves as a date range and the repeatFollowup is the date which will be repeated every month within the time period. I am unable to debug the code as what is causing the delay or is it an infinite loop ?
Any help is appreciated. Thank you
public function calculateDaysOfMonth($startDate, $endDate, $repeatFollowup){
$begin = new \DateTime($startDate);
$end = new \DateTime($endDate);
$repeatDate = new \DateTime($begin->format('Y-m').'-'.date($repeatFollowup));
$days = array();
elseif ($repeatFollowup==30){
$newDate = Carbon::parse('first day of'.$repeatDate->format('Y-m-d'));
//var_dump($newDate->format('Y'));die();
while($repeatDate<=$end){
if($repeatDate->format('m')==2){
$days[] = $newDate->addDays(27);
$newDate->modify('first day of next month')
}
else{
$days[] = $newDate->addDays(29);
$newDate->modify('first day of next month')
}
}
var_dump($days);die();
return $days;
}
}

Answer 1

Yes you are in an infinite loop, because you are never adding to your repeatDate, so it will be always lower (if thats the case) than end, you should do something like:
while($repeatDate<=$end){
if($repeatDate->format('m')==2){
$days[] = $newDate->addDays(27);
$newDate->modify('first day of next month')
}
else{
$days[] = $newDate->addDays(29);
$newDate->modify('first day of next month')
}
$repeatDate->addDays(x);
}