An error occurred while attaching module (Dynamicweb.Frontend.Content)

System.InvalidOperationException: ValueFactory attempted to access the Value property of this instance.
   at System.Lazy`1.CreateValue()
   at System.Lazy`1.LazyInitValue()
   at Dynamicweb.Ecommerce.ProductCatalog.VariantInfoViewModel.CalculatePrice()
   at System.Lazy`1.CreateValue()
   at System.Lazy`1.LazyInitValue()
   at Dynamicweb.Ecommerce.ProductCatalog.VariantInfoViewModel.CalculatePriceMin()
   at System.Lazy`1.CreateValue()
   at System.Lazy`1.LazyInitValue()
   at Dynamicweb.Ecommerce.Frontend.Renderer.RenderVariantInfo(Template template, VariantInfoViewModel variantInfo, RenderingContext renderingContext, Dictionary`2 quantityLookup, Boolean isFakeVariant)
   at Dynamicweb.Ecommerce.Frontend.Renderer.RenderVariantInfos(Template template, Product product, RenderingContext renderingContext, VariantInfoViewModel parent, Dictionary`2 quantityLookup, Dictionary`2 variantOptionsPerGroup)
   at Dynamicweb.Ecommerce.Frontend.Renderer.RenderVariantInfos(Template template, Product product, RenderingContext renderingContext)
   at Dynamicweb.Ecommerce.Frontend.Renderer.RenderProduct(Product product, Boolean extendedProperties, Template template, Int32 loopCounter, Boolean renderRelated, String productUrl, Int32 quantity, Int32 wishListId, Boolean renderPublicList, Boolean isRecursiveCall, Lazy`1 categoryFieldSorting, Int32 orderLineOfProductCount, RenderingContext renderingContext, String unitId)
   at Dynamicweb.Ecommerce.Frontend.Renderer.RenderProduct(Product product, Boolean extendedProperties, String unitId)
   at Dynamicweb.Ecommerce.Frontend.Frontend.EcomRender()
   at Dynamicweb.Ecommerce.Frontend.Frontend.GetContent()
   at Dynamicweb.Frontend.Content.GetModuleOutput(Paragraph paragraph, PageView pageview)