If one removes the checking of the field names, one can write this also in a more concise way. TIMTOWDY!

my @issues;

while (<DATA>)
{
    push @issues, { Id => $1 } if /^ISSUE\s+(\w{5}\d+)$/;
    $issues[-1]->{$1} = $2     if /^(\w+)\s*:\s+(.+)$/
}

dd \@issues;
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