Failed to upload file via zoho recruit api

Failed to upload file via zoho recruit api

We are trying with api as you describe in this link. https://www.zoho.com/recruit/api-new/api-methods/uploadFileMethod.html#Request_URL we are trying to upload a file to candidate record. Our programming language is PHP. We are geeting this error: 4424Unable to process your request. Please verify whether you have provided proper file Can you please provide us any code example to upload file via api Please help us asap, Thanks