Can't call smart contract functions which require gas fees

Question

The below code interacts with a smart contract and requires gas fees. The problem is that the transaction is failing. It's probably a beginner error I'm making. Because my other functions are working fine. I'm talking about the ones that don't make changes to the contract. I have posted the code and the logs. If something important is missing, just comment on it and I'll add it.
Code -

fun test() {
    val function = Function(
        functionRegisterVote,
        listOf<Type<*>>(Uint256(3)),
        emptyList()
    )
    val txData = FunctionEncoder.encode(function)
    val txManager = RawTransactionManager(web3j, Credentials.create(USER_PRIVATE_KEY))
    //Error thrown at below line
    val txHash = txManager.sendTransaction(
        this.requestCurrentGasPrice(), DefaultGasProvider.GAS_LIMIT, CONTRACT_ADDRESS, txData,
        BigInteger.ZERO
    ).transactionHash
    val receiptProcessor = PollingTransactionReceiptProcessor(
        web3j, TransactionManager.DEFAULT_POLLING_FREQUENCY,
        TransactionManager.DEFAULT_POLLING_ATTEMPTS_PER_TX_HASH
    )
    val txReceipt = receiptProcessor.waitForTransactionReceipt(txHash)
    Log.d(TAG, "transaction receipt = \ngas used = ${txReceipt.gasUsed}")
}

Log -

2022-03-23 19:57:16.771 27224-27374/com.kenetic.blockchainvs W/System.err: org.web3j.protocol.exceptions.ClientConnectionException: Invalid response received: 403; {"jsonrpc":"2.0","id":1,"error":{"code":-32002,"message":"rejected due to project ID settings"}}
2022-03-23 19:57:16.773 27224-27374/com.kenetic.blockchainvs W/System.err:     at org.web3j.protocol.http.HttpService.performIO(HttpService.java:178)
2022-03-23 19:57:16.774 27224-27374/com.kenetic.blockchainvs W/System.err:     at org.web3j.protocol.Service.send(Service.java:48)
2022-03-23 19:57:16.774 27224-27374/com.kenetic.blockchainvs W/System.err:     at org.web3j.protocol.core.Request.send(Request.java:87)
2022-03-23 19:57:16.774 27224-27374/com.kenetic.blockchainvs W/System.err:     at org.web3j.tx.RawTransactionManager.getNonce(RawTransactionManager.java:97)
2022-03-23 19:57:16.775 27224-27374/com.kenetic.blockchainvs W/System.err:     at org.web3j.tx.RawTransactionManager.sendTransaction(RawTransactionManager.java:120)
2022-03-23 19:57:16.775 27224-27374/com.kenetic.blockchainvs W/System.err:     at org.web3j.tx.TransactionManager.sendTransaction(TransactionManager.java:125)
2022-03-23 19:57:16.775 27224-27374/com.kenetic.blockchainvs W/System.err:     at com.kenetic.blockchainvs.block_connector.contract.contract_interface.VoteContractAccessor.test(VoteContractAccessor.kt:127)
2022-03-23 19:57:16.775 27224-27374/com.kenetic.blockchainvs W/System.err:     at com.kenetic.blockchainvs.block_connector.contract.contract_interface.VoteContractDelegate.testingFunction(VoteContractDelegate.kt:114)
2022-03-23 19:57:16.776 27224-27374/com.kenetic.blockchainvs W/System.err:     at com.kenetic.blockchainvs.ui.ContractScreenFragment$applyBinding$1$6$1.invokeSuspend(ContractScreenFragment.kt:112)
2022-03-23 19:57:16.776 27224-27374/com.kenetic.blockchainvs W/System.err:     at kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith(ContinuationImpl.kt:33)
2022-03-23 19:57:16.776 27224-27374/com.kenetic.blockchainvs W/System.err:     at kotlinx.coroutines.DispatchedTask.run(DispatchedTask.kt:106)
2022-03-23 19:57:16.777 27224-27374/com.kenetic.blockchainvs W/System.err:     at kotlinx.coroutines.scheduling.CoroutineScheduler.runSafely(CoroutineScheduler.kt:571)
2022-03-23 19:57:16.777 27224-27374/com.kenetic.blockchainvs W/System.err:     at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.executeTask(CoroutineScheduler.kt:750)
2022-03-23 19:57:16.778 27224-27374/com.kenetic.blockchainvs W/System.err:     at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.runWorker(CoroutineScheduler.kt:678)
2022-03-23 19:57:16.778 27224-27374/com.kenetic.blockchainvs W/System.err:     at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.run(CoroutineScheduler.kt:665)