Hi
I have this error when trying to authenticate in free tier api
$ curl -s -X POST 'https://api-free.deepl.com/v2/usage' -H 'Authorization: DeepL-Auth-Key [API_KEY]'
{"message":"Missing Authorization header, expected 'Authorization: DeepL-Auth-Key <API key>'. You can find more info in our docs: https://developers.deepl.com/docs/getting-started/auth"}
or in deepl-cli:
$ deepl init
Welcome to DeepL CLI! Let's get you set up.
✔ Enter your DeepL API key: [API_KEY]
Validating API key...
Error: Invalid API key: Authentication failed with DeepL API
Suggestion: Run: deepl init (setup wizard) or deepl auth set-key <your-api-key>
My recently created API KEY is Active in https://www.deepl.com/en/your-account/keys
DeepL-Auth-Key 299....72b77:fx
Subscription number: BTLvj.....eptD
Status: Active
Usage period: March 11, 2026 - April 11, 2026
Subscription fee: Free