Thank you for approaching us.
I have provided below the proper format of the SMTP Setting. Please verify mail configuration in your tomcat context.xml file.
Also, please note that if you donot have the need of authentication, Please make 'mail.smtp.auth=false' also provide proper SMTP details in above format in your tomcat context file.
If you still have issues with mailing please provide error logs so that our developement team can assist you properly.
If you are facing any other issue, Please feel free to contact us. We are happy to help you.