Circular Dependency Issue on Report

In my report, I want to be able to sort a "Month" slicer by Calender sequence instead of Alphabetic sequence. 

I have a single table for my report, and here it is below, with an emphasis on the "Month" column. 

I created an additional column using the SWITCH function:

Month Number = SWITCH([Month],"January",1,"February",2,"March",3,"April",4,"May",5,"June",6,"July",7,"August",8,"September",9,"October",10,"November",11,"December",12)

I'm assuming that it's okay because I didn't get an error message and the Month Number column was successfully created.

See here:

Now, I go to my report, I select the "Month" slicer, and then select the field "Month".  My goal here is to be able to show the "Month" slicer sorted by calendar sequence (Jan, Feb, March...).

Now, I click on Sort By Column, and then select "Month Number".

And then I get an error message:

"A circular dependency was detected: Final Data[Month], Final Data[Month Number], Final Data[Month]."

I would be so appreciative if someone could provide me with some guidance.

Thank you in advance for your consideration.

Best,

Stephen