diff --git a/contracts/logic/FactoryBase.sol b/contracts/logic/FactoryBase.sol
index 24463ac..ab8f857 100644
--- a/contracts/logic/FactoryBase.sol
+++ b/contracts/logic/FactoryBase.sol
@@ -4,10 +4,10 @@ pragma solidity 0.8.10;
 contract FactoryBase {
   struct ShardParam {
     address to;
-    uint256 tokenId;
+    uint256 nftId;
     address payToken;
-    uint256 tokenAmount;
+    uint256 payAmount;
     uint256 startTime;
     uint256 saltNonce;
   }
-}
\ No newline at end of file
+}
diff --git a/contracts/logic/MinterFactory.sol b/contracts/logic/MinterFactory.sol
index 74a9a49..37f9e59 100644
--- a/contracts/logic/MinterFactory.sol
+++ b/contracts/logic/MinterFactory.sol
@@ -206,21 +206,21 @@ contract MinterFactory is Ownable, FactoryBase, TimeChecker, Initializable, HasS
         // Check payment approval and buyer balance
         IERC20 paymentContract = IERC20(param.payToken);
         require(
-            paymentContract.balanceOf(param.to) >= param.tokenAmount,
+            paymentContract.balanceOf(param.to) >= param.payAmount,
             "MinterFactory: doesn't have enough token to mix shard"
         );
         require(
-            paymentContract.allowance(param.to, address(this)) >= param.tokenAmount,
+            paymentContract.allowance(param.to, address(this)) >= param.payAmount,
             "MinterFactory: doesn't approve MinterFactory to spend payment amount"
         );
         // transfer money to address
         paymentContract.safeTransferFrom(
             param.to,
             feeToAddress,
-            param.tokenAmount
+            param.payAmount
         );
         shard.burnBatch(param.to, ids, amounts);
-        mint721NFT(param.to, param.tokenId, nft);
+        mint721NFT(param.to, param.nftId, nft);
         useSignature(signature);
     }
 
@@ -281,9 +281,9 @@ contract MinterFactory is Ownable, FactoryBase, TimeChecker, Initializable, HasS
             abi.encodePacked(
                 param.to, 
                 nftAddress,
-                param.tokenId, 
+                param.nftId, 
                 param.payToken,
-                param.tokenAmount,
+                param.payAmount,
                 param.startTime, 
                 param.saltNonce
             );
diff --git a/contracts/logic/UserMinterFactory.sol b/contracts/logic/UserMinterFactory.sol
index 9604793..963feff 100644
--- a/contracts/logic/UserMinterFactory.sol
+++ b/contracts/logic/UserMinterFactory.sol
@@ -182,7 +182,7 @@ contract UserMinterFactory is Ownable, FactoryBase, Initializable {
     uint256 nftId,
     uint8 nftType,
     address payToken,
-    uint256 tokenAmount,
+    uint256 payAmount,
     uint256[] memory ids,
     uint256[] memory amounts,
     uint256 startTime,
@@ -197,7 +197,7 @@ contract UserMinterFactory is Ownable, FactoryBase, Initializable {
       nft = equip;
     }
     ShardParam memory param = ShardParam(
-      to, nftId, payToken, tokenAmount, startTime, saltNonce);
+      to, nftId, payToken, payAmount, startTime, saltNonce);
     try factory.shardMixByUser(
       param,
       ids,