Make sure Onion Skin and Edit Multiple Frames buttons are not pressed.
Sorry btw! I am very very new to this software. Im used to procreate XD Thank you for helping me 🙂
It's very likely then that you have had Auto KeyFrame ON and that is how you have drawn them, adding more lines to the existing ones with each new frame.
Switch Auto KeyFrame OFF and try with a blank new file.
When creating new keyframes, make sure they are blank.