Setting down skull errors

Whenever I try to set down a skull, it always returns this error.

Code:

[01:43:15] [Server thread/CRITICAL]: "Could not pass event 'pocketmine\event\player\PlayerDeathEvent' to 'ParadoxUHC v1.1.0': Call to a member function getName() on null on ParadoxUHC\UHC
[01:43:15] [Server thread/CRITICAL]: Error: "Call to a member function getName() on null" (EXCEPTION) in "/src/pocketmine/nbt/tag/CompoundTag" at line 37

While I have already looked at CompoundTag, I still cannot figure out why.

PHP:

public function onDeath(Death $event){
        $player = $event->getEntity();
        if($this->config->get("pole") === "true"){
            if($player instanceof Player) {
                if ($this->status === self::STATUS_PVP || $this->status === self::STATUS_TP_1 || $this->status === self::STATUS_TELE_1 || $this->status === self::STATUS_TP_2 || $this->status === self::STATUS_TELE_2
                    || $this->status === self::STATUS_LAST) {
                    $x = $player->x;
                    $y = $player->y;
                    $z = $player->z;
                    $level = $player->getLevel();
                    $level->setBlock(new Vector3($x, $y, $z), Block::get(Block::NETHER_BRICK_FENCE));
                    $nbt = new CompoundTag("", [
                        new StringTag("id", Tile::SKULL),
                        $this->namedtag->SkullType,
                        new IntTag("x", $x),
                        new IntTag("y", $y),
                        new IntTag("z", $z),
                        $this->namedtag->Rot
                    ]);
                    $tile = Tile::createTile("Skull", $level->getChunk($x >> 4, $z >> 4), $nbt);
                    $level->addTile($tile);
                    $level->setBlock(new Vector3($x, $y+1, $z), Block::get(Block::SKULL_BLOCK));
                }
            }
        }
    }

Fixed the error, but now it is invisible.

PHP:

    public function onDeath(Death $event){
        $player = $event->getEntity();
        if($this->config->get("pole") === "true"){
            if($player instanceof Player) {
                if ($this->status === self::STATUS_PVP || $this->status === self::STATUS_TP_1 || $this->status === self::STATUS_TELE_1 || $this->status === self::STATUS_TP_2 || $this->status === self::STATUS_TELE_2
                    || $this->status === self::STATUS_LAST) {
                    $x = $player->x;
                    $y = $player->y;
                    $z = $player->z;
                    $item = new Item(Item::SKULL);
                    $rot = new ByteTag("Rot", 0);
                    $level = $player->getLevel();
                    $level->setBlock(new Vector3($x, $y, $z), Block::get(Block::NETHER_BRICK_FENCE));
                    $nbt = new CompoundTag("", [
                        new StringTag("id", Tile::SKULL),
                        new IntTag("x", $x),
                        new IntTag("y", $y+1),
                        new IntTag("z", $z),
                        new ByteTag("SkullType", $item->getDamage()),
                        $rot
                    ]);;
                    $chunk = $player->getLevel()->getChunk($x >> 4, $z >> 4);
                    $sk= Tile::createTile(Tile::SKULL, $chunk, $nbt);
                    $level->addTile($sk);
                    $skull = new SkullBlock(3);
                    $player->getLevel()->setBlock(new Vector3($x, $y+1, $z), $skull, true, true);
                }
            }
        }
    }

I have also tried, $skull->place(/*parameters*/);

Why does positions differ from

PHP:

new Vector3($x, $y, $z)


with this one

PHP:

new IntTag("x", $x),
new IntTag("y", $y+1),
new IntTag("z", $z),


Look at this SkullBlock.php

Already did look at that.