heroku e envio de email ao finalizar compra

oi, alguém passou por isso? o envio de email pelo tomcat ocorre ok mas no heroku dá erro de autenticação... será algum bloqueio do gmail a requests da web?

2018-07-05T06:24:49.459971+00:00 heroku[router]: at=info method=GET path="/resources/css/museo-500.ttf" host=cdcspring-apratti.herokuapp.com request_id=115390ec-693f-4dd3-a398-45e7e2c0aad5 fwd="177.13
3.156.65" dyno=web.1 connect=0ms service=8ms status=404 bytes=1379 protocol=http
2018-07-05T06:24:51.092628+00:00 app[web.1]: Pagamento efetuado com sucesso
2018-07-05T06:24:52.665487+00:00 app[web.1]: Erro genérico acontecendo
2018-07-05T06:24:52.665872+00:00 app[web.1]: org.springframework.mail.MailAuthenticationException: Authentication failed; nested exception is javax.mail.AuthenticationFailedException: 534-5.7.14 <http
s://accounts.google.com/signin/continue?sarp=1&scc=1&plt=AKgnsbsP
2018-07-05T06:24:52.665875+00:00 app[web.1]: 534-5.7.14 TEvJ_QHeB8pjIPlESWDJCdZ1F-xsShRaqFUM_R9UEIaase58QEsb438codxJN18Ok25fKC
2018-07-05T06:24:52.665876+00:00 app[web.1]: 534-5.7.14 b9TjsVZKHYwr7rr_KQuPf90o9WkAH2ReMdfwXaGKjmYJrO-E-NmXPKeByu3krSk3rg31Dw
2018-07-05T06:24:52.665878+00:00 app[web.1]: 534-5.7.14 _Ez3UDtmbQzYS8sa-_wJUZCoXZ-G3kLGvnOiW4Fj5gJqVN_z3nyJ81EgMK9IJC4SL6Vuja
2018-07-05T06:24:52.665879+00:00 app[web.1]: 534-5.7.14 Lb2ynIsdeyAyVoR-oMwsUeQPRxXhc> Please log in via your web browser and
2018-07-05T06:24:52.665881+00:00 app[web.1]: 534-5.7.14 then try again.
2018-07-05T06:24:52.665883+00:00 app[web.1]: 534-5.7.14  Learn more at
2018-07-05T06:24:52.665884+00:00 app[web.1]: 534 5.7.14  https://support.google.com/mail/answer/78754 f4-v6sm3608025qti.83 - gsmtp
2018-07-05T06:24:52.665917+00:00 app[web.1]:
2018-07-05T06:24:52.666030+00:00 app[web.1]: at org.springframework.mail.javamail.JavaMailSenderImpl.doSend(JavaMailSenderImpl.java:400)
2018-07-05T06:24:52.666089+00:00 app[web.1]: at org.springframework.mail.javamail.JavaMailSenderImpl.send(JavaMailSenderImpl.java:308)
2018-07-05T06:24:52.666148+00:00 app[web.1]: at org.springframework.mail.javamail.JavaMailSenderImpl.send(JavaMailSenderImpl.java:297)
2018-07-05T06:24:52.666207+00:00 app[web.1]: at br.com.casadocodigo.loja.controllers.PagamentoController.enviaEmailCompraProduto(PagamentoController.java:63)
2018-07-05T06:24:52.666269+00:00 app[web.1]: at br.com.casadocodigo.loja.controllers.PagamentoController.lambda$finalizar$0(PagamentoController.java:44)
2018-07-05T06:24:52.666328+00:00 app[web.1]: at org.springframework.web.context.request.async.WebAsyncManager$4.run(WebAsyncManager.java:322)
2018-07-05T06:24:52.666387+00:00 app[web.1]: at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
2018-07-05T06:24:52.666451+00:00 app[web.1]: at java.util.concurrent.FutureTask.run(FutureTask.java:266)
2018-07-05T06:24:52.666509+00:00 app[web.1]: at java.lang.Thread.run(Thread.java:748)
2018-07-05T06:24:52.666696+00:00 app[web.1]: Caused by: javax.mail.AuthenticationFailedException: 534-5.7.14 <https://accounts.google.com/signin/continue?sarp=1&scc=1&plt=AKgnsbsP
2018-07-05T06:24:52.666698+00:00 app[web.1]: 534-5.7.14 TEvJ_QHeB8pjIPlESWDJCdZ1F-xsShRaqFUM_R9UEIaase58QEsb438codxJN18Ok25fKC
2018-07-05T06:24:52.666700+00:00 app[web.1]: 534-5.7.14 b9TjsVZKHYwr7rr_KQuPf90o9WkAH2ReMdfwXaGKjmYJrO-E-NmXPKeByu3krSk3rg31Dw
2018-07-05T06:24:52.666701+00:00 app[web.1]: 534-5.7.14 _Ez3UDtmbQzYS8sa-_wJUZCoXZ-G3kLGvnOiW4Fj5gJqVN_z3nyJ81EgMK9IJC4SL6Vuja
2018-07-05T06:24:52.666703+00:00 app[web.1]: 534-5.7.14 Lb2ynIsdeyAyVoR-oMwsUeQPRxXhc> Please log in via your web browser and
2018-07-05T06:24:52.666705+00:00 app[web.1]: 534-5.7.14 then try again.
2018-07-05T06:24:52.666706+00:00 app[web.1]: 534-5.7.14  Learn more at
2018-07-05T06:24:52.666708+00:00 app[web.1]: 534 5.7.14  https://support.google.com/mail/answer/78754 f4-v6sm3608025qti.83 - gsmtp
2018-07-05T06:24:52.666739+00:00 app[web.1]:
2018-07-05T06:24:52.666799+00:00 app[web.1]: at com.sun.mail.smtp.SMTPTransport$Authenticator.authenticate(SMTPTransport.java:826)
2018-07-05T06:24:52.666857+00:00 app[web.1]: at com.sun.mail.smtp.SMTPTransport.authenticate(SMTPTransport.java:761)
2018-07-05T06:24:52.666914+00:00 app[web.1]: at com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:685)
2018-07-05T06:24:52.666973+00:00 app[web.1]: at javax.mail.Service.connect(Service.java:295)
2018-07-05T06:24:52.667031+00:00 app[web.1]: at org.springframework.mail.javamail.JavaMailSenderImpl.doSend(JavaMailSenderImpl.java:397)
2018-07-05T06:24:52.667097+00:00 app[web.1]: ... 8 more
2018-07-05T06:24:52.977936+00:00 heroku[router]: at=info method=POST path="/pagamento/finalizar" host=cdcspring-apratti.herokuapp.com request_id=0cbe9d4b-a3cb-4a47-83f9-4adffe08c850 fwd="177.133.156.6