Hi @colivier74 
, welcome to the community forum.
It looks like your website is hosted with OVH and may be using their Load Balancer product.
I believe the OVH load balancer is intercepting your HTTP-01 challenge request and responding with its own key authorization (you can get a hint that’s what is happening because the expected key auth and the received key auth have the same challenge token but a different account thumbprint).
This problem comes up fairly often for OVH users, for e.g.:
- PLESK error - The key authorization file from the server did not match this challenge
- Certificate with loadbalancer on OVH
I don’t think its possible to use OVH’s Load Balancer and the Certbot image with HTTP-01 challenges together. You’ll have to let OVH manage your certificates or disable the load balancer that is swallowing up the HTTP-01 challenge request before your Certbot container has a chance to respond.
Hope that helps!