System.InvalidOperationException: Sequence contains no elements
at System.Linq.ThrowHelper.ThrowNoElementsException()
at System.Linq.Enumerable.Single[TSource](IEnumerable`1 source)
at RMuseum.Services.Implementation.GanjoorService.GetTajikPageByUrlAsync(String url, Boolean catPoems) in C:\Users\hamidreza\source\repos\ganjoor\GanjoorService\RMuseum\Services\Implementation\GanjoorService-Partials\GanjoorService-Tajik.cs:line 144