Trying to send transactions via a signer using my private key

Question

I am making a casino for a client and I want to setup a wallet which will be used to pay for gas for all the information being uploaded on the contract.

I am using the private key to create a signer and then sending the transaction but for some reason the transaction is not being formed.

async function sendToContract() {
    try {
      const provider = new ethers.providers.Web3Provider(window.ethereum);
  
      // Create a wallet instance from the private key
      const wallet = new ethers.Wallet(privateKey, provider);
  
      // Get the signer from the wallet instance
      const signer = wallet.connect(provider); 
      const signer1 = provider.getSigner(); 
      console.log(signer, signer1);
  
      const contract = new ethers.Contract(contractAddress, abi, signer);
      console.log("Contract:", contract);
  

      await contract.setWithdrawAmount(ethers.utils.parseEther(String(user.unclaimed)), user.walletId).then((res)=>{console.log(res)}).catch((err)=>{console.log(err)});
  
    } catch (err) {
      console.log(err);
    }
  }

What am I doing wrong?

I am using ethers v5.7.2 Thanks! :)

Tried all chatbots and could find no info online.