created linode instance with API call but not able to connect to server

It looks like the StackScript you deployed has resulting in your being locked out of the server. StackScript 10079 disables the root user and creates a new user based on a github user with the given username - the resulting user will have the same name and keys as the github user given in stackscript_data.gh_username. In this case, you've provided a gh_useranme of "linode", and since you don't have those keys you can't access the server.

To recover from this, you could either delete this Linode Instance and redeploy, or rebuild the Linode Instance into a different configuration.

To Delete and Redeploy

To Delete this Linode through the API, make these calls:

export TOKEN="my-api-token"
export LINODE_ID=(this linode's ID)

curl -H "Authorization: Bearer $TOKEN" -X DELETE \
   https://api.linode.com/v4/linode/instances/$LINODE_ID

You can then use the same API call you used to deploy this Linode to deploy a new one, but this time either don't include a stackscript_id (if you don't want root login disabled) or change the gh_username to the username of your own github user and ssh in as that user (for example, my github username is "dorthu", so I would ssh in as dorthu@<ip-address>.

Rebuild Linode Instance

The above approach will result in you receiving a new IP Address for the new Linode Instance. If the IP Address you have now is important, a rebuild will redeploy the same Instance with a new Image.

To rebuild through the API, make this API call:

export TOKEN="my-api-token"
export LINODE_ID=(this linode's ID)

curl -H "Content-type: application/json" \
    -H "Authorization: Bearer $TOKEN" \
    -X POST \
    https://api.linode.com/v4/linode/instances/$LINODE_ID/rebuild \
    -d '{"image":"linode/centos7",
         "root_pass":(omitted),
         "authorized_keys":[(omitted)]}'

Once the rebuild finishes, you should be able to log into your Linode as normal.

If you don't want to use the API directly, you can accomplish either of these tasks through the Linode Cloud Manager or the Linode CLI.

Hey Thanks Smith………….its solved now…………..i have omitted "stackscriptid": 10079, "stackscriptdata": {
"gh_username": "linode"
},

from body request and created new instance now I am able to login to this server.

Thanks alot!!! hurray ………I was stuck in it from last 4 days.
Thanks

Glad I could help!