Unfortunately, I was informed that we make way too many Alexa API requests and the reason is excessive polling and/or setting device states. In the past I have added a warning that polling through the Alexa Smarthome Node -> Query must be avoided. There is now a rate limit of 5 minutes enforced, meaning that a specific request can only be performed every 5 minutes. The same goes for setting a device's state. Different requests (e.g. query state of Device1, set state of Device2, query state of Device3) will still work at the same time, but each of them individually can only be performed every 5 minutes.
Screenshot shows what you'll see in case a request was performed too often:
Full Changelog: 5.0.22...5.0.23