Functions involving sending emails for verification/password reset not working

Description:

The email confirmation and password recovery emails aren't being sent. The error is "Error: Message failed: 550 Message was not accepted -- it contains invalid headers. More specifically, the 'From:' header must match the user you are sending mail from." Test emails and emails for new user registrations are being sent and received successfully.
SMTP settings are configured; I've attached a screenshot.

Steps to reproduce:

For example, go to the RocketChat page and click "Forgot your password?" Enter the email address of the user registered in RocketChat and click "Send instructions" The logs show error 550: Message was not accepted -- it contains invalid headers. More specifically, the 'From:' header must match the user you are sending email from.

Expected behavior:

An email with a link to reset the password should be sent to the user.

Actual behavior:

Error

Server Setup Information:

• Version of Rocket.Chat Server: 8.2.1
• License Type: Community
• Number of Users: 280
• Operating System: Oracle Linux 7
• Deployment Method: docker
• Number of Running Instances: 1
• DB Replicaset Oplog: no
• NodeJS Version: v22.16.0
• MongoDB Version: 8.2.3 / wiredTiger (oplog off)

Client Setup Information

• Desktop App or Browser Version: desktop and web
• Operating System: MacOS Sonoma 14.4

Additional context

Settings smtp

Start by tracing the password-reset and email-confirmation mail paths and comparing them with the working test and new-user-registration emails. Check how the SMTP From header is selected and reproduce the failure from the Forgot your password flow; done means both verification and password-recovery messages are accepted and delivered.