need to convert old NBT code to lastest

I have this old nbt code that working on 3.0.0-alpha3 but now i'm using 3.0.4 , so how to convert this code pls, thanks

PHP:

                    $heldItem = $sender->getInventory()->getItemInHand();
                    if($heldItem->getNamedTag()){
                        $nbt = new NBT(NBT::LITTLE_ENDIAN);
                        $nbt->setData($heldItem->getNamedTag());
                    }

error when use it on 3.0.4:

Code:

[17:22:31] [Server thread/CRITICAL]: Error: "Cannot instantiate abstract class p
ocketmine\nbt\NBT" (EXCEPTION) in "plugins/Source-RPGMobs/src/NORA/RPGMobs/Comma
nds" at line 99

 

https://github.com/pmmp/PocketMine-MP/pull/1775

https://forums.pmmp.io/threads/adapting-old-code-using-compoundtags-since-api-3-0-0-alpha12.5975/

 

I'm not really know how to fix this problem, please show me the fixxed code, thanks

 

https://forums.pmmp.io/threads/adapting-old-code-using-compoundtags-since-api-3-0-0-alpha12.5975/