algosdk.error.AlgodHTTPError: broadcast queue full

I am sending them one-at-time with a short delay (0.1 S). I tried to add more delay between sending them, but it did not help. The maximum would be still 100 transactions.
This is the method I use to send transactions:

def call_app(algod_client, private_key, index, app_args):
    sender = account.address_from_private_key(private_key)
    params = algod_client.suggested_params()
    txn = transaction.ApplicationNoOpTxn(sender, params, index, app_args)
    signed_txn = txn.sign(private_key)
    tx_id = signed_txn.transaction.get_txid()
    transactionsList.append(tx_id)
    algod_client.send_transactions([signed_txn])