src/Amadeus/Client/ResponseHandler/Air/HandlerRetrieveSeatMap.php
public static function decodeProcessingLevel($level)
    {
        $decoded = null;

        $map = [
            0 => 'system',
            1 => 'application'
        ];

        if (array_key_exists($level, $map)) {
            $decoded = $map[$level];
        }

        return $decoded;
    }
public static function decodeProcessingLevel($level)
    {
        $decoded = null;

        $map = [
            0 => 'system',
            1 => 'application'
        ];

        if (array_key_exists($level, $map)) {
            $decoded = $map[$level];
        }

        return $decoded;
    }
Decode error processing level code

@param int|string $level
@return string|null