1, the training menu is not reasonable enough. Try to change the training mode, training combination or weight bearing degree, number of groups and so on.
2. The coordination between diet and rest is not reasonable enough. Increase the intake of animal protein in the diet, rest for 2-3 days a week, and make reasonable arrangements.
It is also possible that you lost fat and gained muscle, but the weight of these two parts is similar.
In addition, muscle growth is also relatively slow. Don't imagine that there will be earth-shaking changes in three months. You can also judge the effect of exercise by looking in the mirror in the most intuitive way.