Fonts mixing with Elementor

My setup is as follows:

GP Premium + Elementor

My goal is to have Montserrat as Headings (that works across the whole site) and Lato for the body text.

On all the elementor pages this works perfectly fine (even though I am not using the elementor default fonts)
The blog preview page (built with elementor) works too.
The blog posts itself doesn't "work", it uses Montserrat across the whole post, not only in the headings.

I've been fiddling around for the past hour tried disabling plugins, changing the configuration, changed fonts in elementor and in wordpress, sometimes with the premium module turned off and sometimes with the module turned on.

I just need someone to find my stupid mistake.

Thanks in advance