Not expected HTTP response:Status-Code: 200

When I try to run my backup manually I get the ‘not responded for 10 seconds. Please check information.’ response.

On checking the information I see ‘Not expected HTTP response:Status-Code: 200’.

The debug info shows:
WordPress version: 5.0
BackWPup version: 3.6.6
PHP version: 5.5.38 (64bit)
MySQL version: 10.1.35-MariaDB
cURL version: 7.19.7
cURL SSL version: NSS/3.27.1
WP-Cron url: https://www.sfgroup.com/wp-cron.php
Server self connect: Not expected HTTP response:
Status-Code: 200
Date: Wed, 12 Dec 2018 13:12:25 GMT
Server: Apache
Last-modified: Thu, 22 Nov 2018 07:42:12 GMT
Etag: “0-57b3c01363763”
Accept-ranges: bytes
Content-length: 0
Content-type: text/html
X-backend-server: Array

Document root: /home/sites/1b/6/6a89aa2cfe/public_html/
Temp folder: /home/sites/1b/6/6a89aa2cfe/public_html/wp-content/uploads/backwpup-f90aaf-temp/
Log folder: /home/sites/1b/6/6a89aa2cfe/public_html/wp-content/uploads/backwpup-f90aaf-logs/
Server: Apache
Operating System: Linux
PHP SAPI: cgi-fcgi
Current PHP user: 6a89aa2cfe
Maximum execution time: 0 seconds
BackWPup maximum script execution time: 30 seconds
Alternative WP Cron: Off
Disabled WP Cron: Off
CHMOD Dir: 0755
Server Time: 13:12
Blog Time: 13:12
Blog Timezone:
Blog Time offset: 0 hours
Blog language: en-US
MySQL Client encoding: utf8
PHP Memory limit: 512M
WP memory limit: 40M
WP maximum memory limit: 512M
Memory in use: 46.75 MB
Loaded PHP Extensions:: Core, PDO, PDO_Firebird, PDO_ODBC, Phar, Reflection, SPL, SimpleXML, bcmath, bz2, calendar, cgi-fcgi, ctype, curl, date, dba, dom, enchant, ereg, exif, fileinfo, filter, ftp, gd, gettext, gmp, hash, iconv, imap, interbase, intl, ionCube Loader, json, ldap, libxml, mbstring, mcrypt, mhash, mssql, mysql, mysqli, mysqlnd, odbc, openssl, pcre, pdo_dblib, pdo_mysql, pdo_pgsql, pdo_sqlite, pgsql, posix, pspell, readline, session, snmp, soap, sockets, sqlite3, standard, tidy, tokenizer, xml, xmlreader, xmlrpc, xmlwriter, xsl, zip, zlib

I have seen previous responses advising that “define(‘ALTERNATE_WP_CRON’ , true );” should be added into the wp-config before the “/* That’s all, stop editing! Happy blogging. */” line but when I do this all I get is a blank page when I try to run the backup.

Please advise.