I just found out an error.

I create a Vultr server. I explored all the addons and forgot to disable the SMTP addon when I enabled it. I had no intention to use it just to see what addons Cloudways have. Later that week when I was installing new wordpress I found out that my postfix email doesnt work anymore. After I figured it out with your cloudways support I disabled it. However the email still didn't work. I have tried to reset a dummy username to get a new password to check and also create a new username to get a notification of the new username and password.
So what I was suggested to create a new server and try to see if this happens again when SMTP addon is disabled.
So my understanding that if you don't want to use the SMTP you can disabled it and Cloudways infrastructure should re-configure the server so postfix should work as normal but in this case it doesn't.