Hello Jatin,

if you use Odoo Online or Odoo sh, a standard mail server is provided, which is necessary for incoming and outgoing communication - however, the daily limits may vary: "The standard daily email limit varies between 5 and 200 emails. The exact limit depends on several factors: 1. Type of database subscription (a free app, trial version, paid subscription) 2.Installed applications (e.g. email marketing, marketing automation) 3. If a database migration is in progress" (https://www.odoo.com/documentation/18.0/applications/general/email_communication/faq.html#email-issues-outgoing-delivery-failure-messages-limit

You can view the daily limit at any time via the command line - if the daily limit is reached, outstanding messages are postponed to the next day.

If the limit bothers you, you can either contact Odoo S.A. with a request to increase the limit or connect your own mail server (https://www.odoo.com/documentation/18.0/applications/general/email_communication/email_servers_outbound.html)

Regards,
Chris Dominiak (Intero Technologies GmbH)