Please configure the “SMTP TLS” property to TRUE, so that you can eliminate the issue you have attached.
Make sure that you have provided access to less secure apps to your account in your Google Mail server.
Please follow the steps to enable the access from you Google Mail.
· Next to "Access for less secure apps," select Turn on as mentioned in below screenshot.
· Once you Turned on the access, Please restart the “Put Email” processor to reflect the changes.
Please let us know if you have further assistance.