Hello, confirmed, it was an issue of the firewall ...

original problem : just tried to star the H2 challenge, but got an error, maybe need to do the aqora challenge not behind our firewall ... currently I get aqora template h2-groundstate-energy ⠁ Fetching competition... ⠉ Fetching competition... ⠙ Fetching competition... ⠙ Downloading competition template...
Oh no! Failed to download data: error sending request for url (https://s3.fr-par.scw.cloud/aqora-prod-private/[... deleted...]2522a85024ab5cbec9d08e): error trying to connect: invalid peer certificate: UnknownIssuer