Font combination Issue in preview mode across breakpoints in Figma Site

I’ve created my site with 4 breakpoints. When I use a combination of font styles (Inter Regular + Inter Semibold) within a single paragraph, In the editor mode, it looks perfectly fine. But in preview mode, the text appears different and in irregular size across breakpoints (except primary)

Need help how to fix it? Not sure if it’s a bug or if I’m making a mistake?