Emails are not being sent

I have done everything mentioned in the below links:
https://simple-membership-plugin.com/forums/forum/simple-membership-plugin/
https://simple-membership-plugin.com/forums/topic/premium-membership-registration-issue/

However, emails are still not being sent.
// I’m using “local by flywheel” as a WordPress test environment before going to production.
// I have disabled other plugins to check if there any conflicts, but issue persists.
// Other user registration plugins are being sent without issues.

Is there any fix?