I haven’t used my Amazon Kindle for about a week. I just came to turn it on today, and it was stuck at one of the standby screens. I did the mini-reset of holding the power button for 5 seconds, releasing, waiting a few seconds, and trying the power again. Still nothing. I tried the “longer” reset of holding the power button for 15 seconds… still nothing.
It’s then that I noticed on the Amazon Kindle troubleshooting page, that you should try charging the Kindle, and then repeating the steps. I plugged my Kindle in to begin the charging, and low and behold 5 minutes later it’s my list of Collections.