Nullable value type may be null.

Use IHeaderDictionary.Append or the indexer to append or set headers. IDictionary.Add will throw an ArgumentException when attempting to add a duplicate key. (https://aka.ms/aspnet/analyzers)

Use IHeaderDictionary.Append or the indexer to append or set headers. IDictionary.Add will throw an ArgumentException when attempting to add a duplicate key. (https://aka.ms/aspnet/analyzers)

Dereference of a possibly null reference.

The variable 'total' is assigned but its value is never used

The variable 'total' is assigned but its value is never used

Dereference of a possibly null reference.

Converting null literal or possible null value to non-nullable type.

Nullable value type may be null.