global class BankAccValidation {
    @Future(callout=true) 
    public static void bankAccountValidation(String redirectFlowId) {
        Messaging.SingleEmailMessage mail = new Messaging.SingleEmailMessage();
        mail.setSenderDisplayName('Salesforce Support');
        mail.setSubject('Test');
        mail.setPlainTextBody('Test Body');
        List<String> sendTo = new List<String>();
        sendTo.add('aditi@gmail.com');
        mail.setToAddresses(sendTo);       
        Messaging.SendEmailResult[] result=Messaging.sendEmail(new Messaging.SingleEmailmessage[] {mail});
        if (result[0].success) {
            System.debug('The email was sent successfully.');
        } else {
            System.debug('The email failed to send: '+ result[0].errors[0].message);
        }
    }    
}
A email sent log for reference:::::::::::::
USER_DEBUG|[13]|DEBUG|Email for Customer:::Messaging.SendEmailResult[getErrors=();isSuccess=true;]
This is a sample code, which we from which I am trying to send an email.

1. But email is not being received on any emailId. (Site guest user is sending email here).
2. Also in logs it is showing success, no exception generated.
3. When calling this method from developer console email is being received on specified emailId.

global class BankAccValidation {
    @Future(callout=true) 
    public static void bankAccountValidation(String redirectFlowId) {
        Messaging.SingleEmailMessage mail = new Messaging.SingleEmailMessage();
        mail.setSenderDisplayName('Salesforce Support');
        mail.setSubject('Test');
        mail.setPlainTextBody('Test Body');
        List<String> sendTo = new List<String>();
        sendTo.add('aditi@gmail.com');
        mail.setToAddresses(sendTo);       
        Messaging.SendEmailResult[] result=Messaging.sendEmail(new Messaging.SingleEmailmessage[] {mail});
        if (result[0].success) {
            System.debug('The email was sent successfully.');
        } else {
            System.debug('The email failed to send: '+ result[0].errors[0].message);
        }
    }    
}
A email sent log for reference:::::::::::::
USER_DEBUG|[13]|DEBUG|Email for Customer:::Messaging.SendEmailResult[getErrors=();isSuccess=true;]
This is a sample code, which we from which I am trying to send an email.

1. But email is not being received on any emailId. (Site user is sending email here).
2. Also in logs it is showing success, no exception generated.

global class BankAccValidation {
    @Future(callout=true) 
    public static void bankAccountValidation(String redirectFlowId) {
        Messaging.SingleEmailMessage mail = new Messaging.SingleEmailMessage();
        mail.setSenderDisplayName('Salesforce Support');
        mail.setSubject('Test');
        mail.setPlainTextBody('Test Body');
        List<String> sendTo = new List<String>();
        sendTo.add('aditi@gmail.com');
        mail.setToAddresses(sendTo);       
        Messaging.SendEmailResult[] result=Messaging.sendEmail(new Messaging.SingleEmailmessage[] {mail});
        if (result[0].success) {
            System.debug('The email was sent successfully.');
        } else {
            System.debug('The email failed to send: '+ result[0].errors[0].message);
        }
    }    
}
A email sent log for reference:::::::::::::
USER_DEBUG|[13]|DEBUG|Email for Customer:::Messaging.SendEmailResult[getErrors=();isSuccess=true;]
This is a sample code, which we from which I am trying to send an email.

1. But email is not being received on any emailId. (Site guest user is sending email here).
2. Also in logs it is showing success, no exception generated.
3. When calling this method from developer console email is being received on specified emailId.