If you want to be happy don't open this game, jk besides that for the last group you should be able to see things differently, in such a way that you get rid off the useless blocks, even if it seems like there is a paradox or something between blocks, as if you delete one the other one can not get deleted, well there is another way to do it, search for combinations that will eliminate that one block which is difficult to get rid off, btw every level and group is winnable, altough it may not seem like it.

Recommendation: If your mind gets tired of playing just try doing it another day and get some rest,

You should be able to complete the game in less than 10 hours, just for reference, don't feel pressured.

Good Luck