Process completed with exit code 1.

Nullability of reference types in type of parameter 'memberOptions' of 'ExportMappingExpression<TDestination> ExportMappingExpression<TDestination>.ForColumn<TMember>(string column, Expression<Func<TDestination, TMember>> destinationMember, Action<ExportMemberConfigurationExpression<TDestination, TMember>> memberOptions = null)' doesn't match implicitly implemented member 'ExportMappingExpression<TDestination> IExportMappingExpression<TDestination>.ForColumn<TMember>(string col, Expression<Func<TDestination, TMember>> destinationMember, Action<ExportMemberConfigurationExpression<TDestination, TMember>>? memberOptions = null)' (possibly because of nullability attributes).

Nullability of reference types in type of parameter 'memberOptions' of 'ExportMappingExpression<TDestination> ExportMappingExpression<TDestination>.AddColumn<TMember>(Expression<Func<TDestination, TMember>> destinationMember, Action<ExportMemberConfigurationExpression<TDestination, TMember>> memberOptions = null)' doesn't match implicitly implemented member 'ExportMappingExpression<TDestination> IExportMappingExpression<TDestination>.AddColumn<TMember>(Expression<Func<TDestination, TMember>> destinationMember, Action<ExportMemberConfigurationExpression<TDestination, TMember>>? memberOptions = null)' (possibly because of nullability attributes).

Cannot convert null literal to non-nullable reference type.

Cannot convert null literal to non-nullable reference type.

Non-nullable property 'CellsState' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable field '_sheet' must contain a non-null value when exiting constructor. Consider declaring the field as nullable.

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

Dereference of a possibly null reference.

Possible null reference argument for parameter 'columnName' in 'PropertyMapInfo.PropertyMapInfo(string name, PropertyInfo property, string columnName)'.