I am working on a code, that inserts data to Sql Db from CosmosDb, here is the exception I am facing

I need some help in resolving the following exception:

System.AggregateException
  HResult=0x80131500
  Message=One or more errors occurred. (Object reference not set to an instance of an object.)
  Source=System.Private.CoreLib
  StackTrace:
   at System.Threading.Tasks.Task.ThrowIfExceptional(Boolean includeTaskCanceledExceptions)
   at System.Threading.Tasks.Task.Wait(Int32 millisecondsTimeout, CancellationToken cancellationToken)
   at System.Threading.Tasks.Task.Wait()
   at PushNotificationUserInsert.Program.Main(String[] args) 

This exception was originally thrown at this call stack:

PushNotificationUserInsert.Program.Main.AnonymousMethod__0_0() in Program.cs

Inner Exception 1:
NullReferenceException: Object reference not set to an instance of an object.


in C:\Users\sagajjal\source\repos\ConsoleApp04\ConsoleApp04\Program.cs:line 20