diff --git a/.gas-snapshot b/.gas-snapshot
index 9a138d1..7b3fe98 100644
--- a/.gas-snapshot
+++ b/.gas-snapshot
@@ -1,19 +1,19 @@
-BillboardTest:testApprove() (gas: 195001)
-BillboardTest:testApproveByAttacker() (gas: 165734)
+BillboardTest:testApprove() (gas: 194731)
+BillboardTest:testApproveByAttacker() (gas: 165464)
 BillboardTest:testBid() (gas: 143)
 BillboardTest:testBidByAttacker() (gas: 188)
 BillboardTest:testClearAuction() (gas: 210)
 BillboardTest:testClearAuctionByAttacker() (gas: 144)
-BillboardTest:testGetTokenURI() (gas: 188684)
-BillboardTest:testMintBoard() (gas: 177258)
-BillboardTest:testMintBoardByAttacker() (gas: 19766)
-BillboardTest:testSetBoardProperties() (gas: 301005)
-BillboardTest:testSetBoardProprtiesByAttacker() (gas: 184150)
-BillboardTest:testSetIsOpened() (gas: 48304)
+BillboardTest:testGetTokenURI() (gas: 188414)
+BillboardTest:testMintBoard() (gas: 176988)
+BillboardTest:testMintBoardByAttacker() (gas: 19631)
+BillboardTest:testSetBoardProperties() (gas: 300735)
+BillboardTest:testSetBoardProprtiesByAttacker() (gas: 183880)
+BillboardTest:testSetIsOpened() (gas: 47764)
 BillboardTest:testSetIsOpenedByAttacker() (gas: 11962)
-BillboardTest:testSetTaxRate() (gas: 27454)
+BillboardTest:testSetTaxRate() (gas: 27319)
 BillboardTest:testSetTaxRateByAttacker() (gas: 11992)
-BillboardTest:testTransfer() (gas: 407583)
-BillboardTest:testTransferByAttacker() (gas: 190220)
+BillboardTest:testTransfer() (gas: 407313)
+BillboardTest:testTransferByAttacker() (gas: 189950)
 BillboardTest:testUpgradeAuctionByAttacker() (gas: 13591)
 BillboardTest:testUpgradeRegistryByAttacker() (gas: 13657)
\ No newline at end of file
diff --git a/src/Billboard/BillboardAuction.sol b/src/Billboard/BillboardAuction.sol
index 4940df7..0e87978 100644
--- a/src/Billboard/BillboardAuction.sol
+++ b/src/Billboard/BillboardAuction.sol
@@ -59,9 +59,6 @@ contract BillboardAuction is IBillboardAuction {
     }
 
     modifier isFromOperator() {
-        if (operator == address(0)) {
-            revert OperatorNotFound();
-        }
         if (msg.sender == address(0)) {
             revert InvalidAddress();
         }
diff --git a/src/Billboard/BillboardRegistry.sol b/src/Billboard/BillboardRegistry.sol
index 90bf5c9..a2cff2a 100644
--- a/src/Billboard/BillboardRegistry.sol
+++ b/src/Billboard/BillboardRegistry.sol
@@ -75,9 +75,6 @@ contract BillboardRegistry is IBillboardRegistry, ERC721 {
     }
 
     modifier isFromOperator() {
-        if (operator == address(0)) {
-            revert OperatorNotFound();
-        }
         if (msg.sender == address(0)) {
             revert InvalidAddress();
         }