You have got the "Secondary Sector Informaton" and the "Slot" in there because you're matching everything from "Keep:" to "offset" in your inner while loop, so the first match of $1 in the second block becomes

Phase: 0x7d10  Strength: 31
Secondary Sector Information:
Slot 1:   Keep: 1    -
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I would replace the last while loop with something simpler like

map {
    if ( $_ =~ m/Keep:\s*(\d+)\s*(Phase|offset):\s*([xabcdef\d]+)\s*St
+rength:\s*(\d+)/ ) {
        print "Keep:${1} - ${2}:${3} - Strength:${4}\n";
    }
} split /\r\n|\n/, $line;
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