The following has evaluated to null or missing: ==> categoryName [in template "newsDetail.ftl" at line 61, column 21] ---- Tip: If the failing expression is known to legally refer to something that's sometimes null or missing, either specify a default value like myOptionalVar!myDefault, or use <#if myOptionalVar??>when-present<#else>when-missing. (These only cover the last step of the expression; to cover the whole expression, use parenthesis: (!myDefault, ( ---- ---- FTL stack trace ("~" means nesting-related): - Failed at: #list categoryName.categoryNames as c... [in template "newsDetail.ftl" at line 61, column 14] - Reached through: @article_detail websiteId="${website... [in template "newsDetail.ftl" at line 55, column 11] ----