第六课approve失败

[golds3]

第六课的lock-and-cross task，nft执行授权pool的方法报错了

console.log(link balance now: ${balanceNow}`);

//step2 approve nftLnS
const nft = await ethers.getContract("MyToken", firstAccount);
await nft.approve(nftLnS.target, tokenId)
console.log("approve successful ")`

link balance before: 11000000000000000000
link balance now: 11000000000000000000
An unexpected error occurred:

TypeError: Cannot read properties of undefined (reading 'then')
at ParamType.#walkAsync (/Users/ham/Desktop/project/web3/crosschain-nft/node_modules/ethers/src.ts/abi/fragments.ts:780:20)
at ParamType.walkAsync (/Users/ham/Desktop/project/web3/crosschain-nft/node_modules/ethers/src.ts/abi/fragments.ts:797:24)
at /Users/ham/Desktop/project/web3/crosschain-nft/node_modules/ethers/src.ts/contract/contract.ts:170:22
at Array.map ()
at resolveArgs (/Users/ham/Desktop/project/web3/crosschain-nft/node_modules/ethers/src.ts/contract/contract.ts:169:37)
at populateTransaction (/Users/ham/Desktop/project/web3/crosschain-nft/node_modules/ethers/src.ts/contract/contract.ts:294:36)
at send (/Users/ham/Desktop/project/web3/crosschain-nft/node_modules/ethers/src.ts/contract/contract.ts:313:55)
at Proxy.approve (/Users/ham/Desktop/project/web3/crosschain-nft/node_modules/ethers/src.ts/contract/contract.ts:352:22)
at SimpleTaskDefinition.action (/Users/ham/Desktop/project/web3/crosschain-nft/task/lock-and-cross.js:37:15)
at processTicksAndRejections (node:internal/process/task_queues:105:5)

[QingyangKong]

这几行代码看起来没问题，把其他的和 repo 中的对比一下，检查下是否一致