define( ‘ALTERNATE_WP_CRON’, true ); leads to white/blank page

I was getting the “Job has started, but not responded for 10 seconds” error, so I edited the wp-config.php file to include “define( ‘ALTERNATE_WP_CRON’, true );” before the /* That’s all, stop editing! Happy publishing. */ line.

Now, manually running a backup is leading me to a blank page at wp-cron.php?_nonce=972bcaa259&jobid=1&backwpup_run=runnowalt

Pasted below is the debug info showing that Alternate WP Cron is enabld. Thank you.

WordPress version: 6.0.1
BackWPup version: 3.10.0
PHP version: 7.4.29  (64bit)
MySQL version: 5.7.26-29-log
cURL version: 7.80.0
cURL SSL version: OpenSSL/1.1.1o
WP-Cron url: https://charlottehouse.net/wp-cron.php
Server self connect: Not expected HTTP response:
Status-Code: 200
Server: openresty
Date: Mon, 08 Aug 2022 21:38:09 GMT
Content-length: 0
Strict-transport-security: max-age=31536000; includeSubDomains

Document root: /var/www
Temp folder: /var/www/wp-content/uploads/backwpup-9398ed-temp/
Log folder: /var/www/wp-content/uploads/backwpup-9398ed-logs/
Server: Apache
Operating System: Linux
PHP SAPI: cgi-fcgi
Current PHP user: root
Maximum execution time: 300 seconds
BackWPup maximum script execution time: 30 seconds
Alternative WP Cron: On
Disabled WP Cron: Off
CHMOD Dir: 453
Server Time: 21:38
Blog Time: 14:38
Blog Timezone: America/Los_Angeles
Blog Time offset: -7 hours
Blog language: en
MySQL Client encoding: utf8
PHP Memory limit: 256M
WP memory limit: 40M
WP maximum memory limit: 256M
Memory in use: 4.00 MB
Loaded PHP Extensions:: Core, PDO, Phar, Reflection, SPL, SimpleXML, Zend OPcache, apcu, bcmath, bz2, calendar, cgi-fcgi, ctype, curl, date, dba, dom, exif, fileinfo, filter, ftp, gd, gettext, hash, iconv, igbinary, imagick, intl, json, libxml, mbstring, mcrypt, mysql, mysqli, mysqlnd, openssl, pcntl, pcre, pdo_mysql, posix, pspell, readline, session, shmop, soap, sockets, standard, sysvmsg, sysvsem, sysvshm, tokenizer, wddx, xml, xmlreader, xmlrpc, xmlwriter, xsl, yaml, zip, zlib

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