Welcome to Photrio,
@danielamuntyan !
Sorry to hear your Mju has been giving you problems. In your example images, I see two issues:
* The lighter band along one of the short edges of the frame, which transitions into what seems to be a normal image via a ragged edge
* Colorful 'flames' along a long edge of the frame.
The latter is a sure sign of a light leak somewhere, possibly in the camera. Perhaps the first could be explained from the same, for instance a light leak in the vicinity of the area where the roll sits inside the camera. The ragged line reminds me of the felt light trap in a 35mm cassette.
I'm not familiar with this camera, but does it have some kind of foam light seals?
Has the camera been damaged (e.g. dropped)?