Always sort by x-axis

Hello everyone, I have a problem in sort my line and stacked column chart. 

I use the parameter to switch between week(1-52) and month(1-12) and use it as the x-axis. And the y-axis is the amount. 

The sorting is always swtiched to the amount, when I switch the x-axis. Anyway I can locked the sorting by x-axis. 

Thank you.