ERROR [2] mysqli_connect(): Error while reading greeting packet. PID=12317

  Fatal error in line 5 of file /var/www/vhosts/bibioneonline.eu/httpdocs/includes/mysql_lib.php, PHP 7.4.33 (Linux)

This is the debug trace

Error: "mysqli_connect(): Error while reading greeting packet. PID=12317" (error #2).
Backtrace:
  0: myErrorHandler 
  1: mysqli_connect (line 5 in /var/www/vhosts/bibioneonline.eu/httpdocs/includes/mysql_lib.php)
  2: db_connect (line 72 in /var/www/vhosts/bibioneonline.eu/httpdocs/includes/inc_conn.php)
  3: include_once (line 6 in /var/lib/security/mw_portali/scheda.php)
  4: include (line 1 in /var/www/vhosts/bibioneonline.eu/httpdocs/scheda.php)
Variables in myErrorHandler ():
Client IP: 18.119.11.28
Aborting...