Question: snap_manageAccounts createAccount restricted to allowlisted Snaps?

[bsetec360]

Hi MetaMask team,
I’m building a custom Snap that needs to create and manage smart contract wallet (SCW) accounts inside my Snap and have it appear in the MetaMask Flask UI. I noticed in the docs that snap_manageAccounts supports submethods like [createAccount, list, update, delete] (https://docs.metamask.io/snaps/reference/snaps-api/#createaccount)
below code handle inside the snap using OnKeyringRequestHandler
case "keyring_createAccount": {
const account = {
id: uuidv4(),
type: "eip155:erc4337",
address: "0x6D544390Eb535d61e196c87d6B9c80dCD8628Acd",
scopes: ["eip155:31337"],
options: { name: "My SCW" },
methods: [],
};
await snap.request({
method: "snap_manageAccounts",
params: {
method: "createAccount",
params: account,
},
});
return account;
}}

In frontend using KeyringSnapRpcClient package to initiate createAccount
const client = new KeyringSnapRpcClient(snapId, window.ethereum);
const account = await client.createAccount({}); 

but getting : MetaMask - RPC Error: Method not supported: createAccount
myQuestions are
1.Is it true that only allowlisted Snaps can currently create accounts with snap_manageAccounts?
2.my implementaion is wrong ?
if i am wrong, please give me a correct path to implement.
Note : we are used metamask flask for testing