Weight never stands still. It is either growing, or decreasing, or fluctuating. However, never on site.
During the day, weight fluctuates significantly. Always.
To assess the progress of weight change, you need to consider daily data for at least 1-2 and smooth the curve.
Before answering the question why the weight stands still, you need to figure out which method of losing weight you have chosen. If this is only a diet, then it is necessary to assess the calorie content of the diet, whether it really provides a calorie deficit, which allows you to use fat reserves to meet the needs of the body. Perhaps at first there was a decline, but then you reached a plateau in weight. This is natural, because with a decrease in body weight, the rate of basal metabolism also decreases, and the proper nutrition that you adhered to is no longer hypocaloric. It is necessary to recalculate the calorie content, it should be less.
If the method of losing weight is diet + physical activity, then a plateau in weight could be formed due to the fact that, simultaneously with the expenditure of fat reserves, the body builds up muscle tissue. If the weight stays in place for this reason, which is quite natural and physiological, then it is better to do other exercises, give up strength loads and go on to cardio training. Then the muscles will not grow so actively, and the process of losing weight will go further.
If none of these methods have yielded results, no matter how hard you try, you can lose weight using weight loss drugs. Consult an endocrinologist, he will advise what is right for you.