question

Are you sure the endpoint associated with the service simulator is the same one as that associated with the Echo? (These could come apart if, for example, you have a "live" skill, and are testing a development version.) Also, does this happen all the time? That is, have you tested it with a range of spoken and written requests? Another possibility (if not) is that Alexa is hearing something different than you think (that is, than you're writing in the simulator) and is having trouble handling that specific request. This can happen with, for example, custom slots. If you say a number it will be converted to a digit, while if you type a number ("two") into the simulator, it won't. Neither of these sound all that plausible to me, but they're worth a quick check. Steve