优化

src/main/java/com/izouma/nineth/service/AssetMintService.java

@@ -36,7 +36,7 @@ public class AssetMintService {
     public void mint(Long assetId) {
         Asset asset = assetRepo.findById(assetId).orElseThrow(new BusinessException("asset不存在"));
         User user = userRepo.findById(asset.getUserId()).orElseThrow(new BusinessException("用户不存在"));
-        if (StringUtils.isEmpty(user.getPublicKey())) {
+        if (StringUtils.isEmpty(user.getNftAccount())) {
             NFTAccount account = nftService.createAccount(user.getUsername() + "_");
             user.setNftAccount(account.getAccountId());
             user.setKmsId(account.getAccountKmsId());