[NTG-context] Page printed upside down

Hello, I have printed this document and the page on the back is printed upside down in fact you have to turn the page to read it. How to correct this ? Thank you Fabrice \setuppapersize[A4,landscape] \setuppagenumbering[alternative=,location=] \definemixedcolumns [MyColumns] [ n=2, separator=rule, rulecolor=, balance=yes, ] \setupalign[verytolerant,stretch,hanging] \starttext \startMyColumns \dorecurse{6}{\input knuth} \stopMyColumns \stoptext