SSL handshake failed with Nginx ubantu 10.0 and cloudflare

[Rigal patel]

I have Create SSL certificate using “Let’s Encrypt” in Ubantu 18.10 .i follow below documentation to create SSL certificate.

https://www.linode.com/docs/security/ssl/install-lets-encrypt-to-create-ssl-certificates/

I have check SSL certificate was successfully created I have used below command to test it.

openssl verify chain.pem openssl verify -CAfile chain.pem cert.pem

I have also check ssl connection and its shows connected

openssl s_client -connect example.com:443 -servername example.com

Output
CONNECTED(00000005)

depth=2 C = IE, O = Baltimore, OU = CyberTrust, CN = Baltimore CyberTrust Root

verify return:1

depth=1 C = US, ST = CA, L = San Francisco, O = "CloudFlare, Inc.", CN = CloudFlare Inc ECC CA-2

verify return:1

depth=0 C = US, ST = CA, L = San Francisco, O = "CloudFlare, Inc.", CN = sni.cloudflaressl.com

verify return:1

Nginx config file

server {
    listen         443 ssl;
    listen         [::]:443 default_server;
    # listen 443 ssl; 
    ssl_certificate /etc/letsencrypt/live/example.com/fullchain.pem; 
    ssl_certificate_key /etc/letsencrypt/live/example.com/privkey.pem;

    server_name    example.com www.example.com;
    root           /var/www/html/example.com/public_html;

    location / {
        proxy_pass https://33.34.34.64:443;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection 'upgrade';
        proxy_set_header Host $host;
        proxy_cache_bypass $http_upgrade;
     }
}

But Site not working getting 525 error (SSL handshake failed).In cloudflare ""Universal SSL is Active "

Anyone please suggest possible solution to fix this Issue?

Thanks