Authorization failed when I try to log into gmail using fetchmail

After solving a small problem with starting fetchmail I am faced with another obstacle. This time related to accessing a gmail account through "fetchmail"

I know it's a lot of stuff but I hope someone wants to read this problem that hinders me. Thanks a lot in advance and have a nice day.

I now turn to the description of the problem:

1. First I run the command for the fetchmail test:

   fetchmail -d0 -vk --fetchmailrc /etc/fetchmailrc
   

2. It then starts printing the results of what I believe is a connection with the gmail mail server:

   fetchmail: WARNING: Running as root is discouraged.
   fetchmail: 6.4.2 querying pop.gmail.it (protocol POP3) at Mon Jul 12 17:43:20 2021: poll started
   Trying to connect to 62.141.49.168/995...connected.
   fetchmail: Loaded OpenSSL library 0x1010106f newer than headers 0x1010104f, trying to continue.
   fetchmail: Server certificate:
   fetchmail: Issuer Organization: Let's Encrypt
   fetchmail: Issuer CommonName: R3
   fetchmail: Subject CommonName: mail.gmail.it
   fetchmail: Subject Alternative Name: mail.gmail.it
   fetchmail: Subject Alternative Name: mx1.gmail.it
   fetchmail: Subject Alternative Name: pop.gmail.it
   fetchmail: Subject Alternative Name: smtp.gmail.it
   fetchmail: pop.gmail.it key fingerprint: <key>
   fetchmail: SSL/TLS: using protocol TLSv1.2, cipher <cipher>, <secret stuff>
   fetchmail: POP3< +OK Hello there.
   fetchmail: POP3> CAPA
   fetchmail: POP3< +OK Here's what I can do:
   fetchmail: POP3< TOP
   fetchmail: POP3< USER
   fetchmail: POP3< LOGIN-DELAY 10
   fetchmail: POP3< PIPELINING
   fetchmail: POP3< UIDL
   fetchmail: POP3< IMPLEMENTATION Courier Mail Server
   

3. All that remains is to authenticate the credentials, here comes the error and the closure of the communication:

   fetchmail: POP3> USER dade.marti02gmail.com
   fetchmail: POP3< +OK Password required.
   fetchmail: POP3> PASS *
   fetchmail: POP3< -ERR Login failed.
   fetchmail: Login failed.
   fetchmail: Authorization failure on [email protected]
   fetchmail: For help, see http://www.fetchmail.info/fetchmail-FAQ.html#R15
   fetchmail: POP3> QUIT
   fetchmail: POP3< +OK Better luck next time.
   fetchmail: 6.4.2 querying pop.gmail.it (protocol POP3) at Mon Jul 12 17:43:25 2021: poll completed
   fetchmail: Query status=3 (AUTHFAIL)
   fetchmail: normal termination, status 3
   

I list all the solutions I tried to adopt:

1. Checked the credentials;
2. Domain verified;
3. Tried other communication protocols;
4. 2-Step Verification Removal of Account;
5. Enable third-party app access;
6. Created a special password for access with external apps;
7. All authentication type had been tried.

Nothing at all. The problem was not solved. Since the fetchmail daemon is already running in the background I tried to run "sudo systemctl status fetchmail.service" and the response was similar to that of the test:

    ��� fetchmail.service - LSB: init-Script for system wide fetchmail daemon
         Loaded: loaded (/etc/init.d/fetchmail; generated)
         Active: active (running) since Mon 2021-07-12 17:14:56 CEST; 1min 41s ago
           Docs: man:systemd-sysv-generator(8)
        Process: 1288 ExecStart=/etc/init.d/fetchmail start (code=exited, status=0/SUCCESS)
          Tasks: 1 (limit: 1071)
         Memory: 1.7M
         CGroup: /system.slice/fetchmail.service
                 ������1304 /usr/bin/fetchmail -f /etc/fetchmailrc --pidfile /var/run/fetchmail/fetchmail.pid --syslog
    
    Jul 12 17:14:56 VM-LinuxServer systemd[1]: Starting LSB: init-Script for system wide fetchmail daemon...
    Jul 12 17:14:56 VM-LinuxServer fetchmail[1288]:  * Starting mail retriever agent:
    Jul 12 17:14:56 VM-LinuxServer fetchmail[1288]:    ...done.
    Jul 12 17:14:56 VM-LinuxServer systemd[1]: Started LSB: init-Script for system wide fetchmail daemon.
    Jul 12 17:14:56 VM-LinuxServer fetchmail[1304]: starting fetchmail 6.4.2 daemon
    Jul 12 17:15:01 VM-LinuxServer fetchmail[1304]: Authorization failure on [email protected]
    Jul 12 17:15:01 VM-LinuxServer fetchmail[1304]: For help, see http://www.fetchmail.info/fetchmail-FAQ.html#R15
    Jul 12 17:15:01 VM-LinuxServer fetchmail[1304]: Query status=3 (AUTHFAIL)

I also upload the config file "fetchmailrc":

    set postmaster "root"
    set bouncemail
    set no spambounce
    set properties ""
    set daemon 600
    
    poll pop.gmail.it with proto POP3
       user 'dade.marti02gmail.com' there with password 'secretpwd' is root here;
    stripcr and ssl with sslproto 'tls1.2' and fetchall