"No sent mailbox configured. Please pick one in the account settings." - Mail app not able to send email

I have two NC accounts: account A (admin), and account B (non-admin)

I’m able to send and receive email through the mail app for my account A using A’s specific email (a@email.com)

I’m able to receive but NOT send through the mail app for account B using B’s specific email (b@email.com)

The error the app gives is: Error sending your message No sent mailbox configured. Please pick one in the account settings.

In the admin logs, it says: Error mail Saving draft failed: No drafts mailbox configured

Account B has the same email (b@email.com) registered in its NC account user email field.

What is going on? How can I fix this issue?

Thanks!

Not sure if you got the answer to this, but you will just need to click on the “…” beside the account and select to “Add Mailbox” and then do the same and select account settings to set the default folders for DRAFT, SENT and Deleted items.