Redirect with POST and parameters in a controller
You can't redirect with Post properties. You can only do a request, which you've done. The $response you've created in the controller will contain the results of your HTTP request to the remote service. You'll have to retrieve the the relevant data from that object, and do something with it. You are currently returning that from your function. $response is a Psr\Http\Message\ResponseInterface object. If you just return this, your controller will not know what to do with it.