Contract's state not modifying after connecting with provider.getSigner(address)

[0xadrii]

Hey guys!
I'm currently testing a Smart Contract and I have been dealing with a problem that is driving me crazy.
This test worked perfectly when getting addresses from ethers.getSigners(). However, I have created a file that provides me with he addresses (the exact ones I currently have on my running node).
I have a list of addresses (which are strings). The comments of the code express what is happening.
Here's the code:
`

  await contract.addToWhitelist(addresses[0]);
  await contract.addToWhitelist(addresses[1]);
  await contract.addToWhitelist(addresses[2]);
  
  await contract.safeMintByWhitelisted({
    value: ethers.utils.parseEther("0.0001")
  });
  
  await contract.connect(await provider.getSigner(addresses[1])).safeMintByWhitelisted({
    value: ethers.utils.parseEther("0.0001")
  });
  await contract.connect(await provider.getSigner(addresses[2])).safeMintByWhitelisted({
    value: ethers.utils.parseEther("0.0001")
  });
  
  const buyerZeroBalance = await contract.balanceOf(addresses[0]);
  const buyerOneBalance = await contract.balanceOf(addresses[1]);
  const buyerTwoBalance = await contract.balanceOf(addresses[2]);
  
  expect(buyerZeroBalance).to.equal(1);
  expect(buyerOneBalance).to.equal(1);
  expect(buyerTwoBalance).to.equal(1); 

`
The three addToWhitelist() work fine as they are called from the contract's owner.

contract.safeMintByWhitelisted one works fine too, as addresses[0] is the owner and i can directly call the function without .connect()
Thus, the balance of addresses[0] increases by 1 after minting the token.

The two calls with the .connect don't work, so the balance of addresses[1] and addresse[2] don't increase.

Finally, all balances should be 1 as the three addresses have minted a token. However, just addresses[0] (buyerZeroBalance) has increased.

I think there may be something wrong when calling the function after connecting to the signer, but this works perfectly fine when getting the addresses from ethers.getSigners().

Hopefully someone know what I might have overlooked.
Thank you in advance.