withdraw can't pass the test

[Bouqute]

the withdraw can't pass the test,

My code like this

describe("Withdrawing",()=>{
let balanceBefore;

beforeEach(async()=>{
  // list a item
  transaction = await dappazon.connect(deployer).list(
    ID,
    NAME,
    CATEGORY,
    IMAGE,
    COST,
    RATING,
    STOCK
  )
  await transaction.wait()

  // buy an item
  transaction = await dappazon.connect(buyer).buy(ID,{value:COST})
  await transaction.wait()

  // get deployer balance  before
  balanceBefore = await ethers.provider.getBalance(deployer.address);

  // withdraw
  transaction = await dappazon.connect(deployer).withdraw();
  await transaction.wait()  

})



it("Update the owner balance", async()=>{
  const balanceAfter = await ethers.provider.getBalance(buyer.address);
  expect(balanceAfter).to.be.greaterThan(balanceBefore)
})


it("Update the contract balance", async()=>{
  const result = await ethers.provider.getBalance(deployer.address);
  expect(result).to.equal(0)
})

})

i get the err, the err message like

AssertionError: expected 9994998096167587283777 to be above 9999982111701002581047. The numerical values of the given "ethers.BigNumber" and "ethers.BigNumber" inputs were compared, and they differed.