You may be having trouble because the Android soft user interface keys are positioned on top of the Spell n Link buttons. You'll know this is the case as you'll see the outlines of a triangle, a circle, and a square at the bottom of the screen. The square happens to be on top of the Reset button, while the circle covers part of the Hint button.

You can either wait until these buttons fade away (it takes about five seconds) or you can actively tap a space at the top of the screen or swipe upwards near the top of the screen to quickly hide these buttons.

Then you can use our Hint and Reset buttons again without complications.

NOTE:
These buttons can reappear if you swipe upwards from the bottom of the screen or swipe downwards from the top of the screen. They can also reappear if some background apps cause them to be active again. The key is to be aware of their presence when you need to use a Hint or a Reset.