Phpstorm extract method bug.

I have some code inside a loop like

foreach ($buckets as $platform) {
    foreach ($platform['all_app']['buckets'] as $app) {
        $game = CacheManagerUtil::getGame($app['key']);
        $dayBuckets = $app['day']['buckets'];
        foreach ($dayBuckets as $idx => $row) {
            $day = $row['key_as_string'];
            $amount = $row['amount']['value'];

            // I want to extract the following code
            $amountPer = 0;
            if (isset($row['amount_deriv']) && $idx > 0) {
                $amountDeriv = $row['amount_deriv']['value'];
                $lastDayAmount = $dayBuckets[$idx - 1]['amount']['value'];
                if ($lastDayAmount > 0) {
                    $amountPer = round(($amountDeriv / $lastDayAmount) * 100, 2);
                }
            }
...

When I tried to extract these code, the result is:

list($amountPer, $row) = $this->calAmountPer($row, $idx, $dayBuckets);

public function calAmountPer($row, int $idx, $dayBuckets): array
{
    $amountPer = 0;
    if (isset($row['amount_deriv']) && $idx > 0) {
        $amountDeriv = $row['amount_deriv']['value'];
        // WRONG!!!!
        $lastDayAmount = $dayBuckets;
        if ($lastDayAmount > 0) {
            $amountPer = round(($amountDeriv / $lastDayAmount) * 100, 2);
        }
    }
    return array($amountPer, $row);
}

The $dayBuckets is wrong.

When I only copy the code with out the loop, then extract these code, the result is correct.