title: PayPal REST API: "Client Authentication failed" in sandbox mode
body: <p>I am currently trying to implement the paypal api to get the details of an order, but it shows me the following error:</p>
  <p><strong>Uncaught PayPalHttp\HttpException: {&quot;error&quot;:&quot;invalid_client&quot;,&quot;error_description&quot;:&quot;Client Authentication failed&quot;} in vendor/paypal/paypalhttp/lib/PayPalHttp/HttpClient.php on line 215</strong></p>
  <p>I am using the data that paypal gives me of the client id and the secret that is checked in: <a href="https://developer.paypal.com/developer/applications/" rel="nofollow noreferrer">https://developer.paypal.com/developer/applications/</a> following the official documentation, after i set up my server to make calls to PayPal, im currently following this guide: <a href="https://developer.paypal.com/docs/checkout/reference/server-integration/get-transaction/" rel="nofollow noreferrer">https://developer.paypal.com/docs/checkout/reference/server-integration/get-transaction/</a></p>
  <p>I've been trying to find the solution for two days without much success, do you know why paypal marks this error?</p>
  <p>As a note, I am still in sandbox (the client and the secret are from the sandbox too) and I am using the default application created by paypal, does it have something to do with it?</p>