Error: certificate has expired : renewing certificate doesn't work

[hrishikesh]

I still can’t reproduce it. Maybe you’re affected by this:

Old root certificate of Let's Encrypt TLS certificates for custom domains has expired

Netlify uses a service called Let’s Encrypt to automatically provide the TLS/SSL certificate for your Netlify websites that use custom domains for free. We’re proud to be doing our part to make the web more secure by partnering with Let’s Encrypt. On September 30, 2021, Let’s Encrypt’s root certificate “DST Root CA X3” has expired. This expiration has caused certain browser clients with older operating systems not to be able to load your website as “DST Root CA X3” has expired and “ISRG Root X1…

Though it’s kinda late to be affected by this now.