Text field to be displayed based on single choice select list value

[PS]

Hi, 

I am facing a major issue with this script applied in the behaviours.. .

followed steps: Validator plugin On and given the workflow

In the initialiser and server end added the same script.

Given the mapping correctly.

But still unable to achieve the output.

Need your help!!! 

Select single list field name : Return Adds Media
Drop down values : None, Tran 119, Media, Reverse
Text field: 3 digit Black Customer Code

For Return Adds Media field if we select value "Tran 119" it should display the text field "3 digit Black Customer Code" in the screen.
If we select None or Media or Reverse the text field should be hidden.

import com.atlassian.jira.component.ComponentAccessor

import com.atlassian.jira.ComponentManager

import com.atlassian.jira.issue.fields.customField

import com.atlassian.jira.issue.IssueManager

import com.atlassian.jira.issue.MutableIssue

import com.atlassian.jira.issue.ModifiedValue

import com.atlassian.jira.issue.customfields.manager.OptionsManager

import com.atlassian.jira.issue.fields.config.fieldConfig

import com.onresolve.jira.groovy.user.FieldBehaviours

import com.onresolve.jira.groovy.user.FormField

import com.atlassian.jira.component.ComponentAccessor

FormField RAM = getFeildbyId ("customfield_11413") // id for RAM

FormField dBCC = getFeildbyId ("customfield_15703") // id for dBCC

String RAMchoice = (String) RAM.getValue()

//if (RAMchoice == "Tran 119")  { // this is the RAM choice value

if (RAMchoice.contains("11610")) { // this is the RAM choice value

//FormField dBCC = getFieldBYID("customfield_15703") // id for dBCC

dBCC.setHidden(false)

dBCC.setRequired(true)

}

else {

 dBCC.setHidden(true)

}