No N.A. in my DNA Results, but Consistent Amounts in my Admixture?? (native, Asian)

[Akio]

Autosomal DNA results show:

68% SE Asian
5% NE Asian
24% Central/Western Europe
2% Middle Eastern (North Africa)

However, my Gedmatch in pretty much all tests (Oracle, Chromosome Painting, Individual Chromosome Breakdown), show results for Native American/Amerindian (South, North and Arctic)/Mesoamerican, and Siberian.

For the individual chromosome amounts, some are as high as 8% for Amerindian. The Siberian goes as high as 12% in individual chromosomes. Even when I average out the individual chromosome amounts by adding each one and dividing by 22, it comes up to a substantial amount.

How come it doesn't show up in my DNA test? How old is the admixture?

Thanks!