action error：email action：send email：no form of authorization supported

[HangSue]

Hello, I use postfix+devecot to build an intranet mailbox server, and want to use sentinl for intranet mailbox alarms, but I was told: action error: email action: send email: no form of authorization supported
The version of sentinl is 6.8.4, and the configuration of kibana.yml is as follows
sentinl:
settings:
email:
active: true
user: user #Mailbox user
password: user #Mailbox password
host: ip #Intranet mailbox server
ssl: false