Level 1517 is unbeatable for me!

Whilst watching your video I note that although you have hints switched on you chose to carry out a different move than the one the game suggested. What I have found, again and again, is that IF there is any chance of a lucky board that will help you pass a hard level like this then choosing the first move the game suggests might trigger it. I usually play the first two moves as suggested and then check if any opportunities to create special candies or combos open up. If they do you might have a lucky board, if they don't you probably will fail. The gameboards are fixed like this, so that is what I would recommend. Eventually you should get a lucky board. Sometimes playing pre level starting boosters will trigger a lucky board as well.

That happens a lot! And it is deliberate by the level designers to encourage you to use up your boosters and buy their offers. The algorithm is set to leave players one move or one order short on certain attempts. I find that the only way to enjoy this game is to go with the way the levels are designed. If you are just one lollipop short, use one to pass, because if you don't you will be stuck on that level for a long time. Use the events that allow you to gain boosters by replaying older levels, then save up the boosters for occasions such as this. Many levels leave you a lollipop short. I spend gold bars to buy lollipops so that I can pass those levels. If you are out of gold and boosters then think about taking a two week break from the game. Sometimes they will then lure you back with easy boards and extra moves after an absence.