What is the reason for the error of uploading pictures from the http client of swoole2.1.3?

Development environment

wsl swoole2.1.3

Interface error

there is no problem when using the previous code to call the interface
using swoole asynchronous http often causes the interface to report an error

The proxy server received an invalid response from an upstream server.

Local error

Local errors are often reported

WARNING swConnection_sendfile (ERROR 505): length or offset is invalid.

the code is as follows

$cli = new \Swoole\Coroutine\Http\Client($ip, $port, $ssl);
$cli->set(["timeout" => 1]);
$cli->setHeaders(["Host" => $host]);
$cli->addFile($mergreImg, "merge_file");
$cli->addFile($templateImg, "template_file");
$cli->post("/imagepp/v1/mergeface", [
    "api_key"            => $this->api_key,
    "api_secret"         => $this->api_secret,
    "template_rectangle" => $templateRect,
    "merge_rate"         => $this->merge_rate,
]);
$cli->close();