Postfix has stopped forwarding emails. It is just storing the emails in my user's regular accounts. How do I fix this?

The following line is probably missing or commented out in the main.cfg file:

virtual_alias_maps = hash:/etc/postfix/virtual

You need to do the following:

1.) Add or uncomment that line in the main.cf

2.) Type sudo newaliases

3.) Type sudo /etc/init.d/postfix reload

4.) Type sudo /etc/init.d/postfix restart

This should work to fix the issue.