Please fill out the fields below so we can help you better. Note: you must provide your domain name to get help. Domain names for issued certificates are all made public in Certificate Transparency logs (e.g. https://crt.sh/?q=example.com), so withholding your domain name here does not increase secrecy, but only makes it harder for us to provide help.
I ran this command: Wordpress plug-in Really Simple Security using dns verification
It produced this output:
Terms & Conditions are accepted.
Successfully retrieved account
Successfully verified DNS records
Certificate not created. The order is invalid, possibly due to too many failed authorisation attempts. Please start at the previous step. As your order will be regenerated, you'll need to update your DNS text records
My web server is (include version): apache 2.4.68
The operating system my web server runs on is (include version): linux 4.18.0-553.141.2.lve.el8.x86_64
My hosting provider, if applicable, is: 123 reg
I can login to a root shell on my machine (yes or no, or I don't know): I can get to a shell, haven't checked whether it root or not
I'm using a control panel to manage my site (no, or provide the name and version of the control panel):
The version of my client is (e.g. output of certbot --version or certbot-auto --version if you're using Certbot):
Additional info. I tried to generate a certificate several times using dns without success. I switched to directory challenge and obtained a certificate for the main domain, but not the sub domains such as mail. I installed the limited certificate so the website is functioning. However, I still need a certificate that covers the subdomains and trying to generate that repeatedly fails.
What was the error you received before getting this one? Because the Let's Encrypt production system will temporarily block you for more than 5 errors in one hour. See: Rate Limits - Let's Encrypt
When you reproduce the original problem please provide as much info as you can. Ideally if there are some logs that show the original error sent to your system by Let's Encrypt that would be great. The error you showed was a "guess" by that WordPress plugin and wasn't provided by Let's Encrypt. You may need to ask the WordPress plugin team where to find those.
The Let's Encrypt Staging system is better for testing but I don't know how to use that with that WordPress plugin.
I hadn't realised that the error message was from the plug-in, not the underlying function. I added a line to the php to display the underlying error, re-ran it, and this time it generated a valid wildcard cerificate. Yay!
The error, whatever it was, has now cleared itself. Now to back out my amemendment.....