Put your "my %player;" inside the while loop. Try with the following code, then uncomment that "my %player;" outside the loop, comment out the inside one and try again.

use Data::Dumper;

use strict;
use warnings;

my @players;
#my %player; 
for my $index (1 .. 10){
    my %player; 
        $player{'a'}=$index;
        push (@players, \%player);
}

print Dumper(\@players);
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