Adobe animate Canvas output file not moving to correct frame when viewing for the second time

Hi everyone, Iam new to Animate cc Canvas coding.

I have created one page in animate cc where it has one button in the main frame, on clicking the button it goes inside the movieclip "popupMC" and stops at frame 2

In frame 2 we have another movie clip "MC_1" which has next and back button on clicking those button it navigates to next frame and previous frame

On clicking the next button at the last frame of the movie clip MC_1 it stops at frame 3 of the movieclip "popupMC" where we have the end credit.

And I have a menu button on clicking that i will take us to the main frame

The functionality is not working in the below scenario

1. Click the button 1 it goes to movie clip and display the text 1
2. on cliking the next button the text changes from 1 to 5
3. If i click menu button to return to the main screen in the middle of the frame for e.x 4th frame where text 4 is displayed, it navigates to the main frame
4.On clicking the button 1 it goes to the movie clip and display the text 1, but on clicking next button it is moving to the end screen directly from frame 2 where text 1 is displayed.

Couldnt figure out what causing this issue. Kindly help