If you are constantly getting two scatters and can’t catch the third, you can refresh the page hoping that this will revive the game, and if the slot still doesn’t pay, try to grab the third scatter by hitting the "stop” button. Otherwise, you can increase (but not lowering!) the stake for a couple of spins. Ultimately, if this doesn’t give the expected result, go away and resume your game later. If it keeps happening again, that means that the situation is somewhat changed, but not in your favour. Change the slot!