unable to create HTTPS certificate for www.riversidetoastmasters.com

Have been receiving the following message. I've looked at the suggested links, but I'm not sure what I'm looking for and what to do about it.
Thanks, Derek President Riverside Toastmasters #4301

[2022-01-29 08:11:59 GMT, FreeToastHost System Warning]  *** IMPORTANT! ***

NOTE:  We were unable to create / renew a HTTPS certificate for your custom domain: www.riversidetoastmasters.com
This means that you may not be able to access your website using https:// with your custom domain 
name after any existing certificates expire.  

Possible causes may include:
    a. Your DNS records are set up incorrectly.
    b. You are using domain forwarding--it is *not* supported.
    c. Your custom domain has expired.
    d. The custom domain listed in the admin console is no longer being used.
    e. We were unable to connect with the free LetsEncrypt! service to create the certificate.
    
*** Note that the system may remove your custom domain from the database to prevent further invalid
attempts at cert renewals.

You may also access your website via 4301.toastmastersclubs.org

You can check your custom domain's expiration date using:
     who.is/whois/www.riversidetoastmasters.com

You can view your current DNS records using: 
     www.digwebinterface.com/?hostnames=www.r...ns=auth&nameservers=

You can try to troubleshoot your DNS records using: 
     www.dnsstuff.com/tools#dnsReport|type=do...sidetoastmasters.com

Please contact the FreeToastHost support team at support.toastmastersclubs.org for more details and assistance.

- FreeToastHost Support (This is a system generated message.)
 

FreeToastHost runs a renewal program for clubs whose certificates are approaching their expiry date.  Sometimes there is a problem, which yours appears to have had, but it was successful in the following run:

[Sat Feb 5 08:07:29 2022 GMT - Renewal Loop] Cert Expires: Fri May 6 07:07:28 2022 UTC [riversidetoastmasters.com.crt]