Process bounces showing error

Hello team;
I want to view my bounce emails from phplist software.While clicking process bounce i am getting below error
Cannot create POP3 connection to localhost: Can not authenticate to POP3 server: [AUTH] Authentication failed.
Identifying consecutive bounces
Nothing to do
total of 0 subscribers processed
HOw can i resolve this issue.Please help me out

Thanks & Regards

The message is saying that your phpList installation does not login properly to your bounce mailbox.
It can be tricky to get the settings correct, they are in the config.php list of your installation.

The easiest way to test the settings is to look at the mail server log for errors (i.e. dovecot, if you use that for pop connections). Another way to get the settings is to configure a connection to your bounce mailbox using thunderbird or outlook, and that will provide you with the settings that you would need to use in your config.php file.