well, your weight drop, and so your BEE will drop.
but you didn't change your diet to adjust for the different BEE.

hence plateau of the weight.

why are you 135 cm tall ? are you at the age where you are still growing up ?

Incorporate some HIIT workouts or tabata exercise. Avoid ABC and popcorn.

weight drop, energy requirement also drop.

hence you need to eat even less if you want to lose weight.

uhh, 135cm is the avg height for a 10yr old.
its either u are very bad at measuring / extremely short / trolling.

Are you sure you are 135cm?

You need to do more higher intensity exercises as well as bodyweight workouts in order to enhance weight loss.

Your metabolism will dropped when your weight dropped, means your Basal metabolic rate (BMR) dropped because you will lose muscle as well! Not just water and fat.
For example, your food intake is fixed:

First month (When you at 67kg)
Calories in (2000) < Your BMR (2000)+ exercise (500)

Second month (When you at 60kg)
Calories in (2000) < Your BMR dropped (1800) +exercise (450) *weight lose will decrease your calorie usage while exercise*

Third month (When you at 56kg)
Calories in (2000) = Your BMR dropped (1600) +exercise (400)

Conclusion: Only calories deficit can lose weight.

Solution (to achieve calorie deficit):

1) Increase your workout intensity -> burn more calories (HIIT, eg: sprint)
2) Weight training or resistance training -> build more muscles, more muscle mass will give me high BMR (no money to gym? Do it at your home, such as push up, pull up, plank, squat, burpees, high knees and etc)
3) Eat less/no calorie dense food -> decrease calorie in
4) Drink green tea, no sugar please -> increase metabolism, means increase BMR

The progress will be slow but slow progress is still a progress!! Be consistent and stay healthy!

Just my 2 cent