diff --git a/contracts/EventAndErrors.sol b/contracts/EventAndErrors.sol
index 8fc13a3..b78a3fc 100644
--- a/contracts/EventAndErrors.sol
+++ b/contracts/EventAndErrors.sol
@@ -2,7 +2,6 @@
 pragma solidity 0.8.9;
 
 interface EventAndErrors {
-    // bytes32 constant DEPOSIT_ADDED_SIGNATURE =
 
     /// ███ Events ████████████████████████████████████████████████████████████
 
@@ -85,4 +84,7 @@ interface EventAndErrors {
     /// @dev Wished amount to be locked exceeds the limit allowed.
     /// @dev 0x1c18f846
     error AmountNotAllowed();
+    /// @dev Reverts when success return value returns false.
+    /// @dev 0xe10bf1cc
+    error StaticCallFailed();
 }
diff --git a/contracts/p2pix.sol b/contracts/p2pix.sol
index 9e60e33..d3255c6 100644
--- a/contracts/p2pix.sol
+++ b/contracts/p2pix.sol
@@ -150,7 +150,7 @@ contract P2PIX is
     /// from the total `remaining` value.
     /// @dev Locks can only be performed in valid orders.
     /// @param _buyerAddress The address of the buyer of a `_depositID`.
-    /// @param _relayerTarget Target address entitled to the `relayerPremim`.
+    /// @param _relayerTarget Target address entitled to the `relayerPremium`.
     /// @param _relayerPremium The refund/premium owed to a relayer.
     /// @param _amount The deposit's remaining amount wished to be locked.
     /// @param merkleProof This value should be: 
@@ -659,6 +659,11 @@ contract P2PIX is
             returnSize := returndatasize()
             returnValue := mload(0x00)
             _spendLimit := returnValue
+            // reverts if call does not succeed.
+            if iszero(success) {
+                mstore(0x00, 0xe10bf1cc)
+                revert(0x1c, 0x04)
+            }
         }
     }