163 mailbox server to send mail, confirm to start POP3/SMTP service, and set client authorization code
mail.username is not an alias. The following is an incorrect configuration:

spring.mail.username=Dispatch center

Mail.username must be the same as mail.from as the email address. Mail.password is not the email login password, but the authorization code set/generated when the POP3/SMTP service is enabled
correctly configured:

# All email addresses
[email protected]
[email protected]
# Authorization code
spring.mail.password=RKQXXTUNAHUXBWXO