New successful install getting following error with HTTPS: Cannot write to log file: "/opt/librenms/logs/librenms.log"

This is a new installation using Ubuntu 18.04 and Apache. Installation was successful and also added a few devices. Upon configuring HTTPS I get the following at the HTTPS login page:

### Cannot write to log file: "/opt/librenms/logs/librenms.log"

Make sure it exists and is writable, or change your LOG_DIR setting.

SELinux not installed.

/opt/librenms/logs$ ls -lsa
total 76
4 drwxrwxr-x+ 2 librenms librenms 4096 Oct 25 20:58 .
4 drwxrwx–x 29 librenms librenms 4096 Oct 25 17:29 …
4 -rw-rwxr-- 1 librenms librenms 71 Oct 25 17:18 .gitignore
8 -rw-rwxr-- 1 librenms librenms 5569 Oct 25 21:46 access_log
0 -rw-rwxr-- 1 librenms librenms 0 Oct 25 18:33 discovery_wrapper.log
4 -rw-rwxr-- 1 librenms librenms 1600 Oct 25 21:42 error_log
52 -rw-rwxr-- 1 librenms librenms 45431 Oct 25 21:50 librenms.log
0 -rw-rwxr-- 1 librenms librenms 0 Oct 25 14:45 poller_wrapper.log

librenms@ip-10-0-0-76:~$ ./validate.php

Component Version
LibreNMS 1.68-72-gd314f6429
DB Schema 2020_10_21_124101_allow_nullable_ospf_columns (187)
PHP 7.3.23-4+ubuntu18.04.1+deb.sury.org+1
Python 3.6.9
MySQL 10.1.44-MariaDB-0ubuntu0.18.04.1
RRDTool 1.7.0
SNMP NET-SNMP 5.7.3
====================================

[OK] Composer Version: 2.0.1
[OK] Dependencies up-to-date.
[OK] Database connection successful
[OK] Database schema correct

Can anyone suggest what the issue could be? Please let me know what more information I can provide.

Thanks in advance.
Bill.

/etc/apache2/sites-available/librenms.conf:
<VirtualHost *:80>
DocumentRoot /opt/librenms/html/
ServerName

AllowEncodedSlashes NoDecode
<Directory “/opt/librenms/html/”>
Require all granted
AllowOverride All
Options FollowSymLinks MultiViews

Enable http authorization headers

SetEnvIfNoCase ^Authorization$ "(.+)" HTTP_AUTHORIZATION=$1

<FilesMatch “.+.php$”>
SetHandler “proxy:unix:/run/php-fpm-librenms.sock|fcgi://localhost”

<VirtualHost *:443>
DocumentRoot /opt/librenms/html/
ServerName
SSLEngine on
SSLCertificateFile /etc/ssl/certs/localhost.crt
SSLCertificateKeyFile /etc/ssl/private/localhost.key
CustomLog /opt/librenms/logs/access_log combined
ErrorLog /opt/librenms/logs/error_log
AllowEncodedSlashes NoDecode
<Directory “/opt/librenms/html/”>
Require all granted
AllowOverride All
Options FollowSymLinks MultiViews

I couldn’t find any useful information about this error message. The Error message was not useful at all.
At the end I decided to upgrade the OS to 20.04. I’ve used 18.04 for a few years now and was confortable with it’s stability but suspected that I had mixed up the PHP versions and the OS (18.04 and 7.3 respectively). I upgrade to 20.04 and then upgraded all the PHP packages to 7.4. The error message went away. The file permissions are exactly the same as before.