Getting error when sending second message

App is initialised with proper AppId, and anonymous email 

  Zendesk.initialize(appId: "my app id",

            clientId: "my_mobile_sdk_client_id",

            zendeskUrl: "https://rdsupportteam.zendesk.com")

        Support.initialize(withZendesk: Zendesk.instance)

         let identity = Identity.createAnonymous(name: "Test name", email: "testemail@gmail.com")

        Zendesk.instance?.setIdentity(identity)

When we start a conversation the first message is sent ok, but the second one fails always, and when entering this conversation from the native list view controller, we see a black popup "Failed to load comments"

The UI used to send messages is Zendesk native, like so:

let vc = RequestUi.buildRequestUi()

The request list view controlller behavior is the same.

Any help is much appreciated. Thanx