Sending data using curl

Hello, I want to send my user's data to tappayment to verify them and make them accounts at tappayment and tappayment provided me with a document on how to do so, and in the document, they ask me to send user data using curl

For each document, you need to make a \files request. You will receive a file_id for
each file you upload, you need to use it in creating a business.
Create a File
curl --location --request POST 'https://api.tap.company/v2/files' \
--header 'Authorization: Bearer sk_teqAcdQztv84agVkCBZEup0Hh' \
--header 'Content-Type: multipart/form-data' \
--header 'content-type: multipart/form-data; boundary=---011000010111000001101001' \
--form 'file=""' \
--form 'purpose="identity_document"' \
--form 'title="Commercial License "' \
--form 'expires_at="1913743462"' \
--form 'file_link_create="true"'

and this is the code am using to send the data

$teacher_data = array(
            'purpose' => 'identity_document',
            'file' => '',
            'title' => 'Commercial License ',
            'expires_at' => '1913743462',
            'file_link_create' => 'true'
        );
        $authorization = array(
            'Authorization: Bearer sk_live_k2fxIFGy8KYBWEhV0D97', // test : sk_test_GQJsuwnh5lqcikIrg6tO ,  live : sk_live_kmPRC2fxIFGy8KYBWEhV0D97
            // 'Content-Type: multipart/form-data',
            'Content-Type: application/json; multipart/form-data; boundary=---011000010111000001101001',
        );
$curl = curl_init();
        curl_setopt_array($curl, array(
            CURLOPT_URL => "https://api.tap.company/v2/files",
            CURLOPT_CUSTOMREQUEST => "POST",
            CURLOPT_POSTFIELDS => $teacher_data,
            CURLOPT_HTTPHEADER => $authorization,
        ));

        $response = curl_exec($curl);
        return $response;

and this is the response am getting

{"errors":[{"code":"10000","description":"file param required"},{"code":"10001","description":"purpose param required"},{"code":"10002","description":"file link data create param required"}],"timestamp":1663571602}

it says all the fields are required and I already sent them with $teacher_data var