Transformation Error

I used a transformation which has custom transformations too.. But it comes an error CMSAbstractTransformation.DataBind]: Object reference not set to an instance of an object.

can you please tell me how to overcome.. what is the wrong with transformation..

My transformation as below

<a href="<%# CMS.DocumentEngine.DocumentHelper.GetDocument(CMS.Helpers.ValidationHelper.GetInteger(Eval("NodeLinkedNodeID"), 0), "en-gb", new CMS.DocumentEngine.TreeProvider(CMS.Membership.MembershipContext.AuthenticatedUser)).NodeAliasPath %>">
<img class="img-responsive" src="<%#GetRangeDefaultImageForFeaturedOrRelated(Eval<int>("NodeLinkedNodeID"))%>" alt=""></li>
 <%#Eval("ItemName") %>
 <%#Eval("ItemCode") %>
 <%#Eval("ItemDescription") %>
 </a>
<input name="txtQty_<%# Eval<int>("NODEID") %>_<%# Eval<int>("SKUID") %>" type="text" size="3" id="txtQty_<%# Eval<int>("NODEID") %>_<%# Eval<int>("SKUID") %>" value="01"></li>
<%# GetCustomerBasedSKUListPriceOfRelatedProduct(Eval<int>("SKUID"))%>
<%# GetCustomerBasedSKUPriceOfRelatedProduct(Eval<int>("SKUID"))%>
<%# GetSKUCustomBuyActions(Eval<int>("SKUID"), Eval<int>("NODEID"),Eval<string>("ItemCode"))%>