Look in the product manual for any mention of resets. Not all have this.
Also, you need to test the TV with another video source and this source on another TV. An all blue screen was common on some sets when the input was on some channel and there was no signal. Let's hope it's something as simple as it's on the wrong channel or input.
i was watching TV some days back all of a sudden the quality of image got worse. this continued for some days . now when i switch on my TV all i get is a blue screen kindly provide with some valuable suggestions? (50 inch hisense )