One email address can not receive the triggered Email

I write the following code to send a triggered email. I use two emails address to test. and find that one email address can receive the triggered email and other can not. I want to know why ?
THANK YOU IN ADVACE !

import wixUsers from ‘wix-users’;
export function button5_click(event) {
let user = wixUsers.currentUser;
let userId = user.id;
wixUsers.emailUser(“RCAMr8Z”, userId)
.then( () => {
console.log(“Triggered email sent”);
} )
. catch ( (err) => {
console.log(err);
} );

}

Triggered emails will not be sent to the email of the site owner I have noticed a lot of times in my work. Could that be the case?

I see. Thank you !