Api Authentication fail - The client credentials are invalid

tegutegu Member Posts: 7


I am developing a Blazor web app (Asp.Net Core 3.1 / C#) which needs to retrieve store items.

As a first step I would like to login (get access/refresh token) in to the app.

I am following this documentation: https://developers.lightspeedhq.com/retail/authentication/access-token/

I have a registered and verified api app. (https://cloud.lightspeedapp.com/oauth/update.php)

1, First I would like to test it with Postman.

I am running the sample,

https://cloud.lightspeedapp.com/oauth/access_token.php ->

On the body I fill out the client_id and client_secret and receiving the following error:


    "error": "invalid_client",

    "error_description": "The client credentials are invalid"


If I remove the '.php' than the page comes up but not able to do anything there in Postman.

2, If I do the same in the web app and call this url (credentials are set):


it redirects me the login page - and after login the same response shows up:

{"error":"invalid_client","error_description":"The client id supplied is invalid"}

Can you tell me what is happening and how to set it up?


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