Web.config transform not working

I've created a new web.config (named Web.Cloud.config ) to transform when publishing to the Azure.

The transformation that I need is the tag <system.serviceModel> entirely.

On the original web.config transform I have:

<?xml version="1.0"?><configuration><connectionStrings>
    ...</connectionStrings><appSettings>
    ...</appSettings><system.web><compilation debug="true" targetFramework="4.5" /><httpRuntime targetFramework="4.5"/> <customErrors mode="Off"/></system.web><system.serviceModel><behaviors><serviceBehaviors><behavior><serviceMetadata httpGetEnabled="true" httpsGetEnabled="true"/><serviceDebug includeExceptionDetailInFaults="true"/></behavior></serviceBehaviors></behaviors></system.serviceModel><system.webServer>
    ...</system.webServer></configuration>

on the Web.Cloud.config I have

<configuration xmlns:xdt="http://schemas.microsoft.com/XML-Document-Transform"><system.serviceModel xdt:Transform="Replace"><behaviors><serviceBehaviors><behavior name="..."><serviceMetadata httpGetEnabled="true" httpsGetEnabled="true"/><serviceDebug includeExceptionDetailInFaults="false"/><serviceCredentials><userNameAuthentication userNamePasswordValidationMode="..."
              customUserNamePasswordValidatorType="..., ..."/></serviceCredentials></behavior></serviceBehaviors></behaviors><bindings><wsHttpBinding><binding name="Binding1"><security mode="..."><message clientCredentialType="UserName"/></security></binding></wsHttpBinding></bindings><services><service behaviorConfiguration=".." name="..."><endpoint address="" binding="..."  bindingConfiguration="..." contract="..." /></service></services><serviceHostingEnvironment aspNetCompatibilityEnabled="true" multipleSiteBindingsEnabled="true" /></system.serviceModel></configuration>

When I click on "Preview Transform" the transformation is executed correctly, the entirely <system.serviceModel> is replaced.

After publishing, using the Cloud Configuration, the transformation its not executed...

What can I be doing wrong?