Error 403 when using indieauth login

Hi!

I’ve tried to implement indielogin on my web site https://alias.erdorin.org and everything seems to work properly, until the very last phase:

1. Go to https://indielogin.com/
2. Enter my blog address in the field
3. I then get to the screen “The app https://indielogin.com/ would like to sign you in as https://alias.erdorin.org/.”
4. Click Authenticate
5. Get a Error 403 in return. “Can’t access requested item. It’s either protected or can’t be read by the server.” (translated from French)

Any idea about what is wrong?

Many thanks in advance!

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