Incorrect canonical and alternate on blog posts

[SleeplessByte]

Describe the bug
Blogs don't get the correct alternates or canonicals.

To Reproduce
Steps to reproduce the behavior:

1. Go to https://www.fronteers.nl/nl/blog/2022/12/wees-niet-slim-en-gebruik-webstandaarden

Expected behavior

<link rel="alternate" hreflang="nl-NL" href="https://www.fronteers.nl/nl/blog/2022/12/wees-niet-slim-en-gebruik-webstandaarden">

Screenshots

<link rel="alternate" hreflang="nl-NL" href="https://www.fronteers.nl/nl/blog/2024/10/nieuwe-website">
<link rel="alternate" hreflang="en-US" href="https://www.fronteers.nl/en/blog/2024/10/nieuwe-website">

More context
The issue is that all blog posts have the same key by default. They should use the permalink instead of key (empty) when the key is empty!