How to fix squares in font with ö ë ü ï characters

Design help General
1

Hello, I’m using Montserrat as a font, but it shows squares with ë ä ö ï characters.

How to fix this?

Edit: I noticed this is with all webflow standard fonts also.

image

Here is my site Read-Only: LINK
(how to share your site Read-Only link)

2

Apparently this is a bug when importing from CSV… I search for all the items with such a character and typed them in again.