diff --git a/addresses.txt b/addresses.txt
index 311e945..53d6d8b 100644
--- a/addresses.txt
+++ b/addresses.txt
@@ -1,26 +1,19 @@
-TESTNET:
+-----------------------------------------------------------------------------------------------
+MAINNET v1:
 
-Registry:
-    - ClassHash: 0x7e616bcaaaaf4d22f756e0cabe0e312b6b8d753451ce0f4f6fc44936aae5ec7
-    - Contract: 0x57cf5b3ac51e9ab1735f0720425d3889ac500fc8deac6567ad8163fd210aa92
+Registry;
+    - ClassHash: 0x2fee320389750aef9d6fe7d95754a75a68d4448c019cee2a34cb6b698972db9
+    - Contract: 0x1b0ef7a47d9db8652f8a9010ecaf3e6537442bfab3afed13449b571fa1da37a
 
 Account:
-    - ClassHash: 0xe01784f9a93db5171ed32eaee0610326969980ecbcc4325753428d8227b96b
-
-Sample NFT:
-    - ClassHash: 0x6eac43a8dbb9431f51797486b08de7234420860d2051fa9bd8e9ce4b6203739
-    - Contract: 0x6aaf25616b3177b62b8aa2212cb19affb7cf52a62d97d260c50c53f13547111
-
-Sample TBA: 
-    - Contract: 0x01d6e561Eb81D2E91c626048e9e324526AD6c63034c8Ef7D605faF082A9673a3
-    - salt: 2030
------------------------------------------------------------------------------------------------
+    - ClassHash: 0x11bc9fabead984d714cf82ec46ffa23f4558f27ae73561542fed9fa8fb510ae
 
-MAINNET:
+------------------------------------------------------------------------------------------------
+MAINNET v2:
 
 Registry;
     - ClassHash: 0x2fee320389750aef9d6fe7d95754a75a68d4448c019cee2a34cb6b698972db9
     - Contract: 0x1b0ef7a47d9db8652f8a9010ecaf3e6537442bfab3afed13449b571fa1da37a
 
 Account:
-    - ClassHash: 0x11bc9fabead984d714cf82ec46ffa23f4558f27ae73561542fed9fa8fb510ae
\ No newline at end of file
+    - ClassHash: 0x499ef439944ff0a477c4ecc14785ad31f4c12300993e1ce6568f9c1f2c24c09
\ No newline at end of file
diff --git a/src/account/account.cairo b/src/account/account.cairo
index 6346b50..0258e11 100644
--- a/src/account/account.cairo
+++ b/src/account/account.cairo
@@ -142,6 +142,9 @@ mod Account {
         // @notice protection mechanism for selling token bound accounts. can't execute when account is locked
         // @param duration for which to lock account
         fn lock(ref self: ContractState, duration: u64) {
+            self._assert_only_owner();
+            let (lock_status, _) = self._is_locked();
+            assert(!lock_status, 'Account: account already locked');
             let current_timestamp = get_block_timestamp();
             let unlock_time = current_timestamp + duration;
             self._unlock_timestamp.write(unlock_time);
diff --git a/tests/test_account.cairo b/tests/test_account.cairo
index 6579b79..3924f17 100644
--- a/tests/test_account.cairo
+++ b/tests/test_account.cairo
@@ -238,7 +238,12 @@ fn test_locking() {
     let dispatcher = IAccountDispatcher { contract_address };
     let lock_duration = 3000_u64;
 
+    // get token owner
+    let token_dispatcher = IERC721Dispatcher { contract_address: erc721_contract_address };  
+    let token_owner = token_dispatcher.ownerOf(u256_from_felt252(1));
+
     // lock account
+    start_prank(CheatTarget::One(contract_address), token_owner);
     start_warp(CheatTarget::One(contract_address), 1000);
     dispatcher.lock(lock_duration);
     stop_warp(CheatTarget::One(contract_address));
@@ -258,7 +263,12 @@ fn test_should_not_execute_when_locked() {
     let dispatcher = IAccountSafeDispatcher { contract_address };
     let lock_duration = 3000_u64;
 
+    // get token owner
+    let token_dispatcher = IERC721Dispatcher { contract_address: erc721_contract_address };  
+    let token_owner = token_dispatcher.ownerOf(u256_from_felt252(1));
+
     // lock account
+    start_prank(CheatTarget::One(contract_address), token_owner);
     start_warp(CheatTarget::One(contract_address), 1000);
     dispatcher.lock(lock_duration);
     stop_warp(CheatTarget::One(contract_address));
@@ -267,13 +277,6 @@ fn test_should_not_execute_when_locked() {
     let test_contract = declare('HelloStarknet');
     let test_address = test_contract.deploy(@array![]).unwrap();
 
-    // get token owner
-    let token_dispatcher = IERC721Dispatcher { contract_address: erc721_contract_address };  
-    let token_owner = token_dispatcher.ownerOf(u256_from_felt252(1));
-
-    // start prank
-    start_prank(CheatTarget::One(contract_address), token_owner);
-
     // confirm call to execute fails
     let mut calldata = array![100];
     let call = Call {
@@ -299,23 +302,72 @@ fn test_should_not_upgrade_when_locked() {
     let dispatcher = IAccountSafeDispatcher { contract_address };
     let lock_duration = 3000_u64;
 
+    // get token owner
+    let token_dispatcher = IERC721Dispatcher { contract_address: erc721_contract_address };  
+    let token_owner = token_dispatcher.ownerOf(u256_from_felt252(1));
+
     // lock account
+    start_prank(CheatTarget::One(contract_address), token_owner);
     start_warp(CheatTarget::One(contract_address), 1000);
     dispatcher.lock(lock_duration);
     stop_warp(CheatTarget::One(contract_address));
 
     let new_class_hash = declare('UpgradedAccount').class_hash;
 
+    // call the upgrade function
+    match dispatcher.upgrade(new_class_hash) {
+        Result::Ok(_) => panic_with_felt252('should have panicked'),
+        Result::Err(panic_data) => {
+            stop_prank(CheatTarget::One(contract_address));
+            panic_data.print();
+            return();
+        }
+    }
+}
+
+#[test]
+fn test_should_not_lock_if_not_owner() {
+    let (contract_address, erc721_contract_address) = __setup__();
+    let dispatcher = IAccountSafeDispatcher { contract_address };
+    let lock_duration = 3000_u64;
+
+    // call the lock function
+    start_prank(CheatTarget::One(contract_address), ACCOUNT2.try_into().unwrap());
+    start_warp(CheatTarget::One(contract_address), 1000);
+    match dispatcher.lock(lock_duration) {
+        Result::Ok(_) => panic_with_felt252('should have panicked'),
+        Result::Err(panic_data) => {
+            stop_prank(CheatTarget::One(contract_address));
+            stop_warp(CheatTarget::One(contract_address));
+            panic_data.print();
+            return();
+        }
+    }
+}
+
+#[test]
+fn test_should_not_lock_if_already_locked() {
+    let (contract_address, erc721_contract_address) = __setup__();
+    let dispatcher = IAccountSafeDispatcher { contract_address };
+    let lock_duration = 3000_u64;
+
     // get token owner
     let token_dispatcher = IERC721Dispatcher { contract_address: erc721_contract_address };  
     let token_owner = token_dispatcher.ownerOf(u256_from_felt252(1));
-
-    // call the upgrade function
+    
+    // lock account
     start_prank(CheatTarget::One(contract_address), token_owner);
-    match dispatcher.upgrade(new_class_hash) {
+    start_warp(CheatTarget::One(contract_address), 1000);
+    dispatcher.lock(lock_duration);
+    stop_warp(CheatTarget::One(contract_address));
+
+    // call the lock function again
+    start_warp(CheatTarget::One(contract_address), 1000);
+    match dispatcher.lock(lock_duration) {
         Result::Ok(_) => panic_with_felt252('should have panicked'),
         Result::Err(panic_data) => {
             stop_prank(CheatTarget::One(contract_address));
+            stop_warp(CheatTarget::One(contract_address));
             panic_data.print();
             return();
         }
@@ -328,7 +380,12 @@ fn test_should_unlock_once_duration_ends() {
     let dispatcher = IAccountDispatcher { contract_address };
     let lock_duration = 3000_u64;
 
+    // get token owner
+    let token_dispatcher = IERC721Dispatcher { contract_address: erc721_contract_address };  
+    let token_owner = token_dispatcher.ownerOf(u256_from_felt252(1));
+
     // lock account
+    start_prank(CheatTarget::One(contract_address), token_owner);
     start_warp(CheatTarget::One(contract_address), 1000);
     dispatcher.lock(lock_duration);
     stop_warp(CheatTarget::One(contract_address));