...doesn't work

I've had this Redmi Note 4 phone for about a year and am generally -ed with it.

In recent months I've noticed the pictures have been coming out "a little fuzzy".
I had a look and found some misty deposit on the cover class for the lens, on the
back cover of the phone.

So, I thought "Ah, just remove the back cover and givvita clean "
Three or four You-tube videos later, I was ready to start... - but I couldn't get
the back cover off no matter what So I stopped trying, and just ran my
finger over the lens cover. Lo! Behold! Sing, ye angels! A little piece of plastic
protective material lifted off and revealed a clear glass cover

Now the pics are good again.

Illustration of the foregoing...
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