No access to HA

So I have lost access to home assistant instance. I cannot access with IP address:portnumber. RPi seems to be up. I can access RPi through samba share. I may have messed up with configuration.
So here is the sequence ,

  1. I started getting certificate errors for my connections. App stopped working. Error was “Certificate created using duckdns+ Let’sEncrypt expired on 4th Oct”.
  2. When I checked logs for duckdns, logs showed that certificate expires on 4th Dec.
  3. So I tried changing the domain name and recreated the certificate. Logs confirmed that new certificate was created.
  4. Client still was showing error for certificate. Certificate details showed previous domain name with 4th Oct as expiry, so basically server was still checking same certificate.
  5. At this point, I was at least able to access HA by ignoring certificate. But then I tried replacing the certificate, removed in step 3.

Now I cannot access HA using internal IP or external domain name. Seems like HA is booting up with certificate file not found error. I can see the logs.

Any help is appreciated.

Shekhar