Php postfix is not sending mails in RHEL 8

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Linux

PHP

I installed postfix for sending mails to the customer from my PHP application. I wrote this in php.ini file

sendmail_path = /usr/sbin/sendmail -t -i

didn't work then I changed it to

sendmail_path = /etc/postfix

Can anybody tell why it's not working. I checked mail logs it's status is mail sent. It doesn't show mail is delivered. Anymore changes I need to do in /etc/postfix/main.cf file? Pls help

What I have tried:

sendmail_path = /etc/postfix