function _delegateOf(address _vault, address _user) internal view returns (address) {
    address _userDelegate;

    if (_user != address(0)) {
      _userDelegate = delegates[_vault][_user];

      // If the user has not delegated, then the user is the delegate
      if (_userDelegate == address(0)) {
        _userDelegate = _user;
      }
    }

    return _userDelegate;
  }
function _delegate(address _vault, address _from, address _to) internal {
    address _currentDelegate = _delegateOf(_vault, _from);
    if (_to == _currentDelegate) {
      revert SameDelegateAlreadySet(_to);
    }

    delegates[_vault][_from] = _to;

    _transferDelegateBalance(
      _vault,
      _currentDelegate,
      _to,
      uint96(userObservations[_vault][_from].details.balance)
    );

    emit Delegated(_vault, _from, _to);
  }
diff --git a/test/unit/Vault/Withdraw.t.sol b/test/unit/Vault/Withdraw.t.sol
index 6a15a59..3cec9e3 100644
--- a/test/unit/Vault/Withdraw.t.sol
+++ b/test/unit/Vault/Withdraw.t.sol
@@ -47,6 +47,36 @@ contract VaultWithdrawTest is UnitBaseSetup {
     vm.stopPrank();
   }
 
+  function testFundsLostForever() external {
+    vm.startPrank(alice);
+    uint256 _amount = 1000e18;
+    underlyingAsset.mint(alice, _amount);
+
+    // Alice deposits as usual
+    _deposit(underlyingAsset, vault, _amount, alice);
+
+    // Alice decides she wants to delegate to bob
+    twabController.delegate(address(vault), bob);
+
+    // Alice now tries to reset her delegation
+    twabController.delegate(address(vault), address(0));
+
+    // At this point the funds are lost!! Alice tries to recover her funds in any way...
+    
+    // Alice tries to delegate back to herself but can't
+    vm.expectRevert();
+    twabController.delegate(address(vault), alice);
+
+    // Alice also can't delegate to any other address
+    vm.expectRevert();
+    twabController.delegate(address(vault), bob);
+    
+    // Alice can't withdraw because her funds have been lost forever :(
+    // Expecting a revert with "DelegateBalanceLTAmount(0, 1000000000000000000000)"
+    vault.withdraw(vault.maxWithdraw(alice), alice, alice);
+    vm.stopPrank();
+  }
+
   function testWithdrawMoreThanMax() external {
     vm.startPrank(alice);
 
diff --git a/src/TwabController.sol b/src/TwabController.sol
index a7e2d51..ae7b9ea 100644
--- a/src/TwabController.sol
+++ b/src/TwabController.sol
@@ -646,6 +646,7 @@ contract TwabController {
    * @param _to the address to delegate to
    */
   function _delegate(address _vault, address _from, address _to) internal {
+    require(_to != address(0), "Cannot delegate back to 0 address");
     address _currentDelegate = _delegateOf(_vault, _from);
     if (_to == _currentDelegate) {
       revert SameDelegateAlreadySet(_to);
