Cannot log in to wp-admin

Last night everything was working fine, this morning my blog is up and running (https://polarbarephotography.com) but I get this error message trying to log in to the admin panel.

Warning: Cannot modify header information – headers already sent by (output started at /home/content/99/6608699/html/wp-content/themes/modularity-lite/functions.php:1) in /home/content/99/6608699/html/wp-includes/pluggable.php on line 890

I already researched and tried looking for spaces in the config.php, functions.php, pluggable.php files using both notepad and textpad – still no luck.

Below is the information from that section of pluggable.php in the wp-includes folder — line 890 is bolded

/**
* Redirects to another page, with a workaround for the IIS Set-Cookie bug.
*
* @link https://support.microsoft.com/kb/q176113/
* @since 1.5.1
* @uses apply_filters() Calls ‘wp_redirect’ hook on $location and $status.
*
* @param string $location The path to redirect to
* @param int $status Status code to use
* @return bool False if $location is not set
*/
function wp_redirect($location, $status = 302) {
global $is_IIS;

$location = apply_filters(‘wp_redirect’, $location, $status);
$status = apply_filters(‘wp_redirect_status’, $status, $location);

if ( !$location ) // allows the wp_redirect filter to cancel a redirect
return false;

$location = wp_sanitize_redirect($location);

if ( $is_IIS ) {
header(“Refresh: 0;url=$location”);
} else {
if ( php_sapi_name() != ‘cgi-fcgi’ )
status_header($status); // This causes problems on IIS and some FastCGI setups
header(“Location: $location”, true, $status);
}
}
endif;

Any help is greatly appreciated, this is getting wicked frustrating.