Custom Font Salient – error 404

Hi all,

i am using Salient as a wordpress theme and try to integrate custom-fonts. I am not a developer, but following these instructions (https://themenectar.ticksy.com/article/9773/). When i add the php-code i will get the error “Could not create snippet. Request failed with status code 404”

Every tools (wordpress, salient, …) are updated. What can it mean and how can i resolve that?

Thanks.
Sascha

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