Please help

Don't worry, your performance dropping a bit while you are gaining knowledge is a normal occurence, and you shouldn't be upset

It's possible that you start being influenced by your recently gained knowledge to such an extent that makes you urge yourself to apply what you've learnt even where and when it's not appropriate to do so; and as you don't feel it has any immediate positive effect over your play, you start thinking it is either useless to study or that there is something wrong with it. If you have been impressed by one of Alekhine's attacks for example, chances are you will force yourself to recreate it in your games, even when it's not possible . Or when there is a much better way that suggests itself, but that you are currently insensible for.

Jean-Jacques Rousseau has written down his experiences of learning chess. When he first got acquainted with the game, he had no previous idea of it, but saw two people playing in a cafe. He asked a player about the rules, then played several games against him, at first being given odds of a piece or pawn, and at the end he was playing so well that he was giving odds to his opponent. After the games he became so interested about chess that he got a book about openings and studied it relentlessly for several days, then returned to the cafe to play the same opponent again. He didn't win a single game, much to his dismay, and recalled all those games to have been played as in a blur.

You will need some time to be able to incorporate your recently gained chess knowledge with the one you already have, because it will inevitably contradict with something you already know or with something you have been assuming so far, or you will simply have to learn when and how to rely on it. Although by studying those great players' games you have learnt some ideas, principles and possible solutions to some chess problems (such as how to attack a badly protected king, what to do against an isolated pawn, etc.) they haven't yet become an integral part of your overall chess reasoning mechanism. To be able to feel an improvement effect, you'll need to "rewrite" your current chess decisionmaking algorithm, to find the place the new knowledge belongs to, to rethink what you already know about similar topics, and to get rid of contradicting information. It sounds elaborate but all it requires is practice, because most of the information will get organized subconsciously.

While you are studying something about chess and you want to practice, play at longer time controls than you are used to in live chess, and spend more time thinking than average in online chess. This way you will be able to more carefully analyze the positions and the possible moves, and will be able to find when and how to incorporate what you've just learnt without being under pressure. Every game played has its goals, and games played while you are studying should have the goal of helping you improve. In them, pay attention to whether and how to use the newly gained knowledge, and how to piece it together with the one you already have; don't worry about results at all, they will be a goal for games you will have time to play later. Also, don't require your new abilities to be immediately applicable, and don't require to have an immediate performance improvement. With time passing, the usage of your gained knowledge will become more and more intuitive, but while studying you should urge yourself neither to make quick but correct (they're inversely proportional) decisions, nor to apply your new knowledge immediately, everywhere and at all costs. Be patient, your performance will improve, give yourself some time

In bodybuilding, for example, people train with one kind of exercises to increase their muscle volume, then they follow up with another period of exercises that "shape" the muscles, and optionally with exercises to increase muscle strength, coordination, etc. In chess it's the same - you get rough knowledge, then you have to make your brain get used to it, and to find out how to properly use its full capabilities.