Warning ErrorHandler PHP 7.0

What this warning means?

MyPackage\Handlers\ErrorHandler::__invoke(Slim\Http\Request $request, Slim\Http\Response $response, Exception $exception)

should be compatible with

Slim\Handlers\Error::__invoke(Psr\Http\Message\ServerRequestInterface $request, Psr\Http\Message\ResponseInterface $response, Exception $exception)

I receive this warning only on a server with PHP 7.0, it’s ok on 5.6.

In your ErrorHandler, what happens if you remove the type hints, or type hint against \Psr\Http\Message\ServerRequestInterface and \Psr\Http\Message\ResponseInterface instead?