Exception after adding this plugin to Grails 3.2.4 app

[anti43]

Caused by: org.springframework.core.serializer.support.SerializationFailedException: Failed to serialize object using DefaultSerializer; nested exception is java.lang.IllegalArgumentException: DefaultSerializer requires a Serializable payload but received an object of type [grails.plugin.springsecurity.LoginController]

grailsVersion=3.2.4

URI /login/auth Class java.lang.IllegalArgumentException Message Cannot serialize; nested exception is org.springframework.core.serializer.support.SerializationFailedException: Failed to serialize object using DefaultSerializer; nested exception is java.lang.IllegalArgumentException: DefaultSerializer requires a Serializable payload but received an object of type [grails.plugin.springsecurity.LoginController] Caused by DefaultSerializer requires a Serializable payload but received an object of type [grails.plugin.springsecurity.LoginController]