Failed to delete the page: [SqlGenerator.GetAutomaticQuery]: Class name 'CMS.AlternativeUrl' doesn't

I use Portal Engine. I can't delete the page because this error occurs:

Exception type: CMS.DataEngine.DataClassNotFoundException Stack trace: at CMS.DataEngine.DataClassInfoProvider.GetDataClassInfo(String name, Boolean throwIfNotFound) at CMS.DataEngine.SqlGenerator.GetAutomaticQuery(String queryFullName) at CMS.DataEngine.QueryInfoProvider.GetQueryInfoInternal(String queryName) at CMS.DataEngine.QueryInfoProvider.GetQueryInfo(String name, Boolean throwException) at CMS.DataEngine.DataQueryBase1.GetConnectionStringName() at CMS.DataEngine.DataQueryBase 1.get_ConnectionStringName() at CMS.DataEngine.Query.QueryBatch.<>c.b__3_0(IDataQuery q) at System.Linq.Lookup2.Create[TSource](IEnumerable1 source, Func2 keySelector, Func2 elementSelector, IEqualityComparer1 comparer) at System.Linq.GroupedEnumerable3.GetEnumerator() at CMS.DataEngine.Query.QueryBatch.d__ 3.MoveNext() at CMS.DataEngine.Query.QueryBatch.Execute() at CMS.DataEngine.ObjectDependenciesRemover.RemoveObjectDependenciesByQuery(IEnumerable1 queries) at CMS.DataEngine.ObjectDependenciesRemover.RemoveObjectDependenciesAuto(BaseInfo infoObj, Boolean deleteAll, Boolean clearCache) at CMS.DataEngine.ObjectDependenciesRemover.RemoveObjectDependencies(BaseInfo infoObj, Boolean deleteAll, Boolean clearCache) at CMS.DataEngine.AbstractInfoBase1.DeleteData() at CMS.DataEngine.BaseInfo.Delete() at CMS.DocumentEngine.TreeNode.DeleteInternal(DeleteDocumentSettings settings) at CMS.DocumentEngine.DocumentHelper.DeleteDocument(DeleteDocumentSettings settings) at CMSModules_Content_CMSDesk_Delete.Delete(Object parameter) in D:\Jenkins\Digitron\CMS\CMSModules\Content\CMSDesk\Delete.aspx.cs:line 809. How to solve this problem.