Hi Rayhan,

It sounds like the issue might be with the way recipients are being added to your campaign. The error message 'Cancelled: No Recipients' typically indicates that, at the time the campaign is set to send, there are no valid recipients in the list you've targeted. Here are a few things to check:

1. List Population: Ensure that the list you're adding the user to is correctly populated and active. Double-check that users are successfully being added to the list before the campaign send job is created.
2. List Filters: If you have any filters or conditions set on your list, make sure that the users you're adding meet these criteria. Otherwise, they may not be included when the campaign is executed.
3. Template Issues: Sometimes, issues with the email template can cause campaigns to cancel. Check if the template is correctly attached and has no errors.
4. User Status: Verify that the users you're adding are not unsubscribed or suppressed due to previous interactions. Campaigns won't send to users who have opted out or been marked as inactive.
5. Timing Conflicts: Make sure there aren't any conflicts with campaign scheduling, such as overlapping send times or restrictions on sending.

It might be helpful to run a test campaign with a small, manually verified list to see if it processes correctly. If the issue persists, checking the logs or error messages for more specific details would be the next step.

Hope this helps!