SUMMARIZE giving wrong value

[gumis_rulez]

Hi,

When I count distinct orderID's the result is 4924.

When I use SUMMARIZE to create new table:

Summary = SUMMARIZE(Orders, Orders[CustomerName], "Total Orders", DISTINCTCOUNT(Orders[OrderId]))

I receive a table, which sum of Total orders gives 4941.

https://drive.google.com/file/d/1yad0B6GVbpARWcdRT9UG4hZ19kW7mb9E/view?usp=sharing 

What is wrong?

[ThxAlot · Accepted solution]

Nothing special, some OrderIds correpsond to multiple customers,