Unable to fetch recordTypeId in lightning component

Question

I am unable to fetch recortype in lightning component. Can anyone help me tell where is the issue

Code for component

<aura:component controller="EMTEventCreationWizardController" implements="lightning:actionOverride,force:lightningQuickAction,flexipage:availableForAllPageTypes,flexipage:availableForRecordHome,force:hasRecordId,lightning:isUrlAddressable" access="global" >
<aura:attribute name="recordId" type="Id"/>
<aura:attribute name="recordTypeId" type="String" />
<aura:attribute name="ObjectName" type="String" default="Events__c" access="global"/>
<aura:attribute name="eventRecordType" type="String"/> 

<aura:if isTrue="{!equals(v.eventRecordType,'Internal Event')}">
    <c:EMT_InternalEvent recordTypeId="{!v.recordTypeId}" eventRecordType="{!v.eventRecordType}" ObjectName="{!v.ObjectName}" recordId="{!v.recordId}"/>
</aura:if>
  <aura:if isTrue="{!equals(v.eventRecordType,'External Event')}">
    <c:EMT_ExternalEvent recordTypeId="{!v.recordTypeId}" eventRecordType="{!v.eventRecordType}" ObjectName="{!v.ObjectName}" recordId="{!v.recordId}"/>
</aura:if>

here is the code for my controller

 doInit : function(component, event, helper) {
    var recordTypeId = component.get("v.pageReference").state.recordTypeId
    console.log("recordType is "+recordTypeId);
    component.set('v.recordTypeId',recordTypeId);


    helper.fetchRecordTypeName(component);


}

Here is the code for helper

fetchRecordTypeName: function(component,event) {
    var action = component.get("c.getRecordTypeNameById");
    action.setParams({
        'objectName': component.get("v.ObjectName"),
        'strRecordTypeId': component.get('v.recordTypeId'),
    });
    action.setCallback(this, function(response) {
        component.set("v.eventRecordType", response.getReturnValue());

    });
    $A.enqueueAction(action);
}

Here is the code for apex controller

 public static String getRecordTypeNameById(String objectName, Id strRecordTypeId)
{
    return Schema.getGlobalDescribe().get(objectName).getDescribe().getRecordTypeInfosById().get(strRecordTypeId).getName();
} 

Kindly let me know where i am getting it wrong

when i am trying to display recordtypeId to console from controller the value i get is undefined