All the steps look correct to me however I'm getting the following error:
curl -X GET https://api.kite.trade/portfolio/holdings -H 'Authorization: token <API key>:<API secret>' -H 'X-Kite-Version: 3'
I regenerated the `API secret` 3 times from the app details console.
"message": "Incorrect `api_key` or `access_token`.",
Use the above link to log into your account, after which you should be getting a request as part of the link it's redirected to. Use that token to generate a session. Using the equivalent of this call in your language of choice
This should give you the access token