Hi, welcome to perlmonks!

First of all: use strict; and use warnings; is great!
This would tell you, that "Global symbol "$Temp" requires explicit package name".
Second: use autodie; or add another or die $!; to line 4.

Why do you open the file twice? You should at least close the filehandle before opening it again.
Closing it before writing to it, does not work either!
Oh, now I understand!!! You use the same filehandle for input and output! That will never work, use two different ones...

open (FILE, "<:encoding(UTF-8)", $Profile) or die $!;
my @Lines = <FILE>;
close(FILE);

open (FILE2, ">", $Profile) or die $!;
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and the end...

  print FILE2 "$Line";
}
close(FILE2);
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