I have the exact problem of front camera not working and hang as a blank screen in my phone after the recent software update .Tried to clear data, force stopped the app, tried restarting, tried factory reset. Nothing worked. So went to nearby Samsung authorized service center. They analysed and said like camera ic is not working and asked me to change the motherboard for the cost of 7000rs. It is not even 1 and half years I bought Samsung M30 and this is highly disappointing.
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