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.
Let's Debug is a very good test site but it does not catch all problems. If you look at the verbose output (link here) you see the info below. Note your domain redirects the original URL for /.well-known/acme-challenge several times.
The last redirect drops the part for /.well-known/acme-challenge/... and so does not return the expected value to the Let's Encrypt server.
You need to review your pattern of redirects. Since you have others that work it will help to compare this one to those
hello, thanks for the help, I solved the problem, the fault was the domain alias pointing to another ip address in the registrar's DNS.
Thanks for your support and keep up the good work