Show us picture of that info screen that indicates that 90%

For Negeri Sembilan, Melacca and Northern Johor, the frequency mux is still the same, which is CH30 (546MHz) and CH32 (562MHz).
If you can get signals before, and now you can't, then that means it is very likely something wrong with your antenna alignment.
Try check and readjust your antenna position, or try place your antenna somewhere else.

If can, show us a picture of your antenna as well.

Judging from the UI, it seems that you are using Sharp LCD TV, am I correct?  :hmm:
What you can do now is, you go to Manual Search there, enter Channel 30 (546MHz), now you see the Strength and Quality readings are 0%, right? Stay on that signal reading page first, don't press Start Scan/Search first.
So now while you monitor closely at the Strength and Quality readings, you go and readjust/realign your antenna position, or try place your antenna somewhere else, until you get signal readings for Strength and Quality readings for Channel 30 (546MHz). You might need a second person to either monitor the signal readings or adjust the antenna to get this done.

Slowly adjust/align the antenna until you can get some readings; try to get as high as possible. Once you see there is signal readings and it is stable (not intermittent or fluctuating), maintain the antenna position (or screw the antenna tightly if using outdoor antenna), and press Start Search/Scan.
Now you should be able to get the TV channels.