Not able to access the value in byte type variable

From last two days I am debugging a C# code. It is a service which generate a code by the locker to write on the tag. Which is shown below: -

 byte[] currentData = null;
            if (lockerVendor == LockerVendor.SchulteSchlagbaumV2 || lockerVendor == LockerVendor.BurgV2 || lockerVendor == LockerVendor.Ojmar)
            {
                PSTec.UWP.Shared.Tools.ErrorHandler.DebugMessage("WriteLockerDataToCard-Method: Start Reading Current Lockerdata on card.");
                //3mal probieren in hf reader klasse
                var result = await readLockerDataFromCarrier(uID);
                if (result == null)
                {
                    PSTec.UWP.Shared.Tools.ErrorHandler.DebugMessage("WriteLockerDataToCard-Method: WriteLockerDataToCard: current data on desired sector is not readable.");
                    return false;
                }
                currentData = result.Item2;
            }

As I am debugging it. I can see the value in uID which is AA835F9C in var result = await readLockerDataFromCarrier(uID); but still debugger goes through

if (result == null)
                {
                    PSTec.UWP.Shared.Tools.ErrorHandler.DebugMessage("WriteLockerDataToCard-Method: WriteLockerDataToCard: current data on desired sector is not readable.");
                    return false;}

It never stores the final value in

currentData = result.Item2;

It would be great help if someone able to point out my mistake.

Thank You, Kushagra