Knoxtane It seems like “Turnstile” extension is preventing registration
flarum.ERROR: GuzzleHttp\Exception\ClientException: Client error: `POST https://challenges.cloudflare.com/turnstile/v0/siteverify` resulted in a `400 Bad Request` response:
{"success":false,"error-codes":["missing-input-secret"],"messages":[]}
It looks like the extension wasn’t configured properly, which is the reason why the issue happened