Unable to sync Search API index schema and Typesense schema. Error: Failed to download model file

The Typesense server itself downloads the model. Can you please post the Typesense logs here?

Can you also post the logs for the Typesense server? Usually, Typesense writes the logs to the standard output

I can't find any logs on the server
How do I set the --log-dir?

You can try with: ddev logs -f -s _name_of_typesense_container_

Thank you Luca
Please see my logs

There are some certificates issues with the download of the model from https://models.typesense.org/public/all-MiniLM-L12-v2/model.onnx.
Maybe something related to your network or the docker image you're using to run Typesense.

Unfortunately is something out of the control of the Drupal module...