There is a certain period in early Mandarin that is very frustrating for learners. You keep learning new words and listening to audio and trying to speak, and yet you feel like you are not improving. Tones slip again, familiar characters disappear, and simple sentences take too long to build. This is often the phase where beginners are ready to throw away their methodology, because they no longer feel that it works; but what is actually happening is that their methodology just needs better targeting. Mandarin does not progress in a linear fashion. Often the only time that the next breakthrough happens is when a weakness is made obvious enough that it becomes a target for targeted study. A plateau is not always a sign of failure. Very often it is a sign that practice needs better focus.
First of all, you should see if your study has been too scattered. Many students will study everything in their studies each day. They will spend five minutes listening, study a handful of words, review a bit of their grammar, and practice speaking. On the surface, this seems very productive, but it will only result in a lack of progress for your Mandarin. Mandarin benefits from a narrower focus of practice. If you have a hard time speaking Mandarin, your speaking session should focus heavily on your speaking for a few days or even for a week. If your reading is very slow, you should focus solely on character and sentence recognition instead of doing other things in your session. Often, when you focus on one particular weakness and repeat it until you realize what is wrong with that weakness, it starts to improve.
Also, many beginners mistakenly think that practicing more will help when they have stalled. They will add more vocabulary, more new dialogues, more long audio to listen to. Often this makes things worse because it will not fix the problem, it will only make the problem more obscure because you are focusing on the next item instead of focusing on the area you are not good at. Instead, what you should do is focus less, and focus on something that you should have been good at, but still struggle with. If you cannot use a sentence structure when you speak, you should not move on to the next item in your textbook; instead you should focus on using that sentence structure correctly over and over again with different words and different scenarios. If your tones are still not that good, you should not try to learn more words; instead you should take a rest from new words for the day and practice saying a handful of words that you already know in sentences. If your character study is not as good as you want it, you should spend more time remembering a smaller quantity of words. You will start improving when you focus on improving one specific weakness, instead of trying to improve everything.
You can also try resetting by focusing specifically on one area that is already not good to start, just for a while. A useful fifteen-minute reset session can help. Spend the first part revisiting some item in your studies such as a single dialogue, six characters, or a specific grammatical pattern. The middle stretch of study you should focus on trying to say and do without looking at the text. That will force you to discover if you can recall or do what you are trying to do. The final minutes you spend should focus specifically on improving what you are currently bad at by repeating it over and over until you are better. This approach works because you are seeing clearly where you have the problem; when a problem is visible, it can be easier to solve.
It also helps if the practice itself has a change to it as well. If you have been trying to study characters by themselves, try writing out some words to start using characters more. If you have been doing silent reviews, switch to reviewing out loud. If you have been doing a ton of listening in general, try listening to a smaller portion and trying to repeat it out loud. Plateaus often feel emotional, but they are often mechanical underneath. If we make a small change in how we study, our brain can get engaged with the study more. You should also reflect on your study. At the end of your practice session you should notice what you have improved on and how you have improved on it and what is still giving you a hard time. This will force you to see where you are, and will not leave you trying to improve too much too fast.
Mandarin often does not progress very quickly all at once, more often there will be specific problems that will get less difficult, and eventually you will feel like you have improved. A plateau in your study is just a time when you know you are not getting anywhere fast, and this will be frustrating, but it is not a bad thing. It is pushing you to focus on what your weak points are, and once that focus starts becoming a problem, the improvements that you make are visible and very noticeable to you, you can notice the tone, you can remember the word, or you can speak faster and longer. That is what you do when you start making progress, which means that you have started to feel more confident and motivated about what you are doing, you are making progress.