Azure Key Vault error message "AKV10000: Request is missing a Bearer or PoP token."

I have Key Vault on Azure and I added Access policies for App registrations with Secret permissions (Get, List, Set, Delete, Recover, Backup, Restore)
I wrote Java code:

    String keyVaultUri = "https://myKeyVault.azure.net";

    ClientSecretCredential paramClientSecretCredential = new ClientSecretCredentialBuilder()
            .clientId("MyApplicationId")
            .clientSecret("MyApplicationSecretKey")
            .tenantId("MyTenantId")
            .build();

     SecretClient secretClient = new SecretClientBuilder()
        .vaultUrl(keyVaultUri)
        .credential(paramClientSecretCredential)
        .httpLogOptions(new HttpLogOptions().setLogLevel(HttpLogDetailLevel.BODY_AND_HEADERS))
        .buildClient();

     KeyVaultSecret storedSecret = secretClient.getSecret("mySecret");

     System.out.println("Secret value: "+storedSecret.getValue());

I'm using these Maven dependencies:

1. azure-security-keyvault-secretss (version 4.6.2)
2. azure-core (version 1.39.0)
3. azure-identity (version 1.9.0-beta.1)

After I started my code I got this error message Status code 401, "{"error":{"code":"Unauthorized","message":"AKV10000: Request is missing a Bearer or PoP token."}}"

Do you have any suggestions on how to fix this?

I made some changes with your code and I got the secrete of my key vault at output.

Code:

import com.azure.identity.ClientSecretCredential;
import com.azure.identity.ClientSecretCredentialBuilder;
import com.azure.security.keyvault.secrets.SecretClient;
import com.azure.security.keyvault.secrets.SecretClientBuilder;
import com.azure.security.keyvault.secrets.models.KeyVaultSecret;

public class KeyVaultKam {
    public static void main(String[] args) {
        String keyVaultUri = "https://<keyvault-name>.vault.azure.net/";
        String secretName = "<secrete-name>";

        ClientSecretCredential credential = new ClientSecretCredentialBuilder()
                .clientId("<client-ID>")
                .clientSecret("<client-secrete>")
                .tenantId("<tenant-ID>")
                .build();

        SecretClient secretClient = new SecretClientBuilder()
                .vaultUrl(keyVaultUri)
                .credential(credential)
                .buildClient();

        try {
            KeyVaultSecret secret = secretClient.getSecret(secretName);
            System.out.println("Secret value: " + secret.getValue());
        } catch (Exception e) {
            System.out.println("Error retrieving secret: " + e.getMessage());
        }
    }
}

pom.xml:

I added below dependencies to the pom.xml file,

<dependencies>
     
        <dependency>
            <groupId>com.azure</groupId>
            <artifactId>azure-security-keyvault-secrets</artifactId>
            <version>4.6.2</version>
        </dependency>
        
        <dependency>
            <groupId>com.azure</groupId>
            <artifactId>azure-core</artifactId>
            <version>1.39.0</version>
        </dependency>
        
        <dependency>
            <groupId>com.azure</groupId>
            <artifactId>azure-identity</artifactId>
            <version>1.4.0</version>
        </dependency>
        
</dependencies>

I created access policy for the client application as below,

Output:

It runs successfully and got the output of my secrete as below,