diff --git a/src/components/chain/contract/Locker.js b/src/components/chain/contract/Locker.js
index aa7d090..6ef4d2f 100644
--- a/src/components/chain/contract/Locker.js
+++ b/src/components/chain/contract/Locker.js
@@ -84,8 +84,8 @@ export class Locker {
     return txHash
   }
   async execUnlock(provider, chainId, nft, tokenIds) {
+    const nftContract = new ethers.Contract(nft, erc721Abi, provider.getSigner())
     for (let tokenId of tokenIds) {
-      const nftContract = new ethers.Contract(nft, erc721Abi, provider.getSigner())
       const owner = await nftContract.ownerOf(tokenId)
       if (owner.toLowerCase() != lockAddressImtbl.toLowerCase() && owner.toLowerCase() != lockAddressMain.toLowerCase()) {
         throw new Error('params mismatch, perhaps one transaction is pending')