It seems like XAMPP is trying to stop Apache and MySQL, but it’s indicating that they are not running. This message typically occurs when XAMPP detects that Apache and MySQL are not currently active processes.

Error :-

Restarting XAMPP for Linux 8.1.25-0...
XAMPP: Stopping Apache...not running.
XAMPP: Stopping MySQL...not running.
XAMPP: Stopping ProFTPD...not running.
XAMPP: Starting Apache...fail.
XAMPP:  Another web server is already running.
XAMPP: Starting MySQL...ok.
XAMPP: Starting ProFTPD...fail.
XAMPP:  Another FTP daemon is already running.

Solutions:-

sudo /opt/lampp/lampp status

Output:-

Version: XAMPP for Linux 8.1.25-0
Apache is not running.
MySQL is running.
ProFTPD is not running.

sudo lsof -i :80

root@ip-172-31-41-118:/opt# sudo lsof -i :80
COMMAND     PID     USER   FD   TYPE   DEVICE SIZE/OFF NODE NAME
apache2 2691659     root    4u  IPv6 12227001      0t0  TCP *:http (LISTEN)
apache2 2748703 www-data    4u  IPv6 12227001      0t0  TCP *:http (LISTEN)
apache2 2748704 www-data    4u  IPv6 12227001      0t0  TCP *:http (LISTEN)

Now kill the pid using below command

sudo kill 2748703

Next to restart the apache server

sudo /opt/lampp/lampp restart

Now its working