how to go back to 'previous' Tactic?


There is a solution. If you launch the tactics trainer from the web app (not sure if it works from your phone, browser, but Chrome on a PC/Mac works), you will find a row of icons representing your recent successes and failures. If you click on any one of them, it will take you to that tactics example and you can review it in unrated mode. See the screen shot below, but please do not laugh at my pathetic results...
The hint button and the next button are in exactly the same place (on mobile) so I misclick by it frequently accident. And then it takes me to the next one and I have no way of solving it. Is there a way to go back to an unsolved tactic? This is driving me crazy!