Problem with certificate

Hello,
I can’t rech my Jitsi website. Error: This is not a secure connection.
Tried to renew with : /usr/share/jitsi-meet/scripts/install-letsencrypt-cert.sh
Error: Failed authorization procedure.my.domain.com

Tried also: certbot renew

Error: Attempting to renew cert (my.domain.com ) from /etc/letsencrypt/renewal/my.domain.com .conf produced an unexpected error: Failed authorization procedure. my.domain.com (http-01): urn:ietf:params:acme:error:connection :: The server could not connect to the client to verify the domain :: Fetching https://my.domain.com/.well-known/acme-challenge/xkOeqJFT9WVTmgNJKtt40DPqVd5HYKorq2woWVD7kE4: Error getting validation data. Skipping.
All renewal attempts failed. The following certs could not be renewed:
/etc/letsencrypt/live/my.domain.com /fullchain.pem (failure)

Error:
All renewal attempts failed. The following certs could not be renewed:
/etc/letsencrypt/live/my-domain.com/fullchain.pem (failure)

Please help. The students have to use jitsi on monday…

Disable firewall temporarily and try to update the cert…

An unexpected error occurred:
There were too many requests of a given type :: Error creating new order :: too many failed authorizations recently: see Rate Limits - Let's Encrypt

May be give it a try after an hour…

Failed authorization procedure. mydomain.com (http-01): urn:ietf:params:acme:error:connection :: The server could not connect to the client to verify the domain :: Fetching https://mydomain.com/.well-known/acme-challenge

Got:
The following errors were reported by the server:

Domain: mydomain.com
Type: connection
Detail: Fetching
https://mydomain.com/.well-known/acme-challenge/RQCoe2i9SUe033memxJCHqMgvtfsVF3S702CrTOdEdI:
Error getting validation data