Squarespace is showing different font type on mobile device

I have a problem, my Squarespace website on mobile device is showing different font type. (In comparison with editor, desktop, iPhone, and Android devices)

And I don't use custom font, I am using default font that is available on Squarespace. 

I use Noto Serif for Japanese Characters.

At first I thought that it does not support Japanese Character so I manually add Google Fonts API: Noto Serif Japanese, and adjust the CSS accordingly.

But it is not changing anything, and the worst part is, the font is showing different font weight in Android device.

I've included some picture so someone can help me identify and maybe solve the problem.

P.S. I've read similar posts but have not found the answer.