linux - Apache can't start - Address already in use - Unable to listen for connections, unable to open logs

I have Debian 9 installation (Bitnami appliance) with Moodle learning system and Lambda theme. We have https enabled. I tried to secure apache server according to best practices and the last two things I changed was adding "FileETag None" in some config files and installed apachetop to monitor web server. I suppose the apachetop installation caused this problem. When I enter the ip in the browser, I get the initial screen of apache web server, but the web page don't work.

When I try to start apache, I get this:

root@debian:/etc# sudo /opt/bitnami/ctlscript.sh start apache

Syntax OK
(98)Address already in use: AH00073: make_sock: unable to listen for 
connections on address [::]:80
(98)Address already in use: AH00073: make_sock: unable to listen for 

connections on address 0.0.0.0:80
no listening sockets available, shutting down
AH00015: Unable to open logs
/opt/bitnami/apache2/scripts/ctl.sh : httpd could not be started
Monitored apache

I tried to search web for the solution, but I did'nt find exactly the same error message. Most answers to similar problems with binding were about killing the second apache processes, but I found only one apache2 listening. I tried this :

root@debian:/etc/apache2/sites-enabled# sudo netstat -ltnp | grep ':80'

tcp6       0      0 :::80                   :::*                    LISTEN      
475/apache2

root@debian:/etc/apache2/sites-enabled# netstat -tulpn | grep apache2
tcp6       0      0 :::80                   :::*                    LISTEN      
475/apache2

root@debian:/etc/apache2/sites-enabled# sudo netstat -ltnp | grep ':443'
root@debian:/etc/apache2/sites-enabled#

I also change the ownership of the log to www-data, but nothing changed.
When I stop apache with this

root@debian:/# /opt/bitnami/ctlscript.sh status apache
apache not running
root@debian:/# netstat -tulpn | grep apache2
tcp6       0      0 :::80                   :::*                    LISTEN      
475/apache2

I can still access the "Apache2 Debian default page" when I enter ip in the browser. Is this normal?

Well, it's working now,

root@debian:/home/bitnami# ps aux | grep apache
root       462  0.0  0.4  75612  4268 ?  Ss   09:04   0:00 /usr/sbin/apache2 -k start
www-data   463  0.0  0.3 364772  4036 ?  Sl   09:04   0:00 /usr/sbin/apache2 -k start
www-data   464  0.0  0.3 364772  4036 ?  Sl   09:04   0:00 /usr/sbin/apache2 -k start
root      1179  0.0  0.0  12784   960 pts/0    S+   09:05   0:00 grep apache

root@debian:/home/bitnami# kill 462
root@debian:/home/bitnami# kill 463
bash: kill: (463) - No such process
root@debian:/home/bitnami# kill 464
bash: kill: (464) - No such process
root@debian:/home/bitnami# kill 1179
bash: kill: (1179) - No such process
root@debian:/home/bitnami# /opt/bitnami/ctlscript.sh start apache
Syntax OK
/opt/bitnami/apache2/scripts/ctl.sh : httpd started at port 80

Monitored apache

I think that kill of the first process got it to work, but after server restart I get the same error message and killing the process and start apache is necessary :(