How to set up the Flance4U API with JavaScript and PHP?
Briefly

The 401 Unauthorized error typically indicates that the application is either using an incorrect or insufficient authorization method. Verify the API key and ensure it has the proper permissions and scopes. Additionally, check the API documentation for any specifics regarding authentication as certain endpoints might have unique requirements or may need additional headers to be sent.
Make sure you have the correct permissions assigned to your API key. Some endpoints may require specific scopes or permissions to access.
Check if the API is expecting additional authentication methods, such as a specific user agent string or additional headers.
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