Parameter Redefinition error in MineschaftPopulator

[Leejit]

Error: Redefinition of parameter $level
File: /plugins/BetterGen-master/src/Ad5001/BetterGen/populator/MineshaftPopulator
Line: 134
Type: E_COMPILE_ERROR

THIS CRASH WAS CAUSED BY A PLUGIN
BAD PLUGIN : BetterGen v1

Code:
[125] // First, filling everything blank.
[126] BuildingUtils::fill($this->level, new Vector3($x, $y, $z - 1 ), new Vector3($x - 4, $y + 2, $z + 1 ));
[127] // Then, making sure the floor is solid.
[128] BuildingUtils::fillCallback(new Vector3($x, $y - 1, $z - 1 ), new Vector3($x - 4, $y - 1, $z + 1 ), function ($v3, $level) {
[129]
[130] if ($level->getBlockIdAt($v3->x, $v3->y, $v3->z ) == Block::AIR)
[131] $level->setBlockIdAt($v3->x, $v3->y, $v3->z, Block::PLANK);
[132] }, $this->level);
[133] // Putting rails
[134] BuildingUtils::fillCallback(new Vector3($x, $y, $z ), new Vector3($x - 4, $y, $z ), function ($v3, $level, $level) {
[135] if ($random->nextBoundedInt(30 ) !== 0) {
[136] $level->setBlockIdAt($v3->x, $v3->y, $v3->z, Block::RAIL);
[137] $level->setBlockDataAt($v3->x, $v3->y, $v3->z, 1);
[138] }
[139] }, $this->level, $random);
[140] // After this, building the floor maintener (the wood structure)
[141] $level->setBlockIdAt($x, $y, $z - 1, Block::FENCE);
[142] $level->setBlockIdAt($x, $y, $z + 1, Block::FENCE);
[143] $level->setBlockIdAt($x, $y + 1, $z - 1, Block::FENCE);
[144] $level->setBlockIdAt($x, $y + 1, $z + 1, Block::FENCE);

Backtrace:
#0 (): pocketmine\Server->crashDump(boolean)

Tesseract version: 0000000000000000000000000000000000000000 [Protocol 107; API 3.0.1]
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OS : Linux, linux

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