Emails are not being sent

First identify the expected message: quote PDF to the customer, quote to the administrator contact, simple-form request or automatic reminder.

For automatic quote emails, check Send an e-mail to customer and Send an e-mail to admin in the module configuration, then save.
Check the selected Administrator contact and its email address. Simple-form requests are sent to this contact; the customer copy depends on the customer-email option.
In Advanced Parameters > Email, check the sending method and use Send a test email. If this message does not arrive either, ask your hosting provider to check PrestaShop’s email configuration.
If the PrestaShop test arrives but the module message does not, check the template and quote language: editing email templates. Keep any error message.
Check the email log if logging is enabled, then check the recipient’s spam folder. A logged sending operation does not guarantee delivery.