Not all letters from my font are appearing

Hi, I use a custom font on this website but somehow if I use the word "koffie" the double "ff" wont't appear. The are a few other letters as well having issues. Anyone know what to do? 

It is on this page: https://digna-brand.squarespace.com/de-hotelleven

PW: Digna12

@tuanphan Can you help me w/this?

I don't see the text "Auto..." https://digna-brand.squarespace.com/de-hotelleven?

Can you add it?

Daar zit je dan.

Onder je systeemplafond. Tapijttegels. Automatenkoffie.

If I copy paste the tekst, I see the right spelling, in the screenshot above you see how it's shown on the website. 

12 hours ago, Lian said:

Daar zit je dan.

Onder je systeemplafond. Tapijttegels. Automatenkoffie.

If I copy paste the tekst, I see the right spelling, in the screenshot above you see how it's shown on the website. 

Maybe problem from custom font, you try contacting font author

Or you can consider change this text only to another font (we can give the code)

for eg, I changed to monospace