# MutantHub mutant #3799: Coinbase nLockTime/nSequence rule gated with DeploymentActiveAt(*pindexPrev): skipped on the first active block
# Repository: bitcoin/bitcoin @ 3f0f142b1d0d08a18152d6b100e12d1abf09d58e
# File: src/validation.cpp:4200-4200
# Review: APPROVED; outcome: SURVIVED
diff --git a/src/validation.cpp b/src/validation.cpp
index 65b652d..d996208 100644
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -4197,7 +4197,7 @@ static bool ContextualCheckBlock(const CBlock& block, BlockValidationState& stat
     }
 
     // Make sure the coinbase transaction is timelocked to the block's height.
-    if (nHeight > 0 && DeploymentActiveAfter(pindexPrev, chainman, Consensus::DEPLOYMENT_CONSENSUSCLEANUP)) {
+    if (nHeight > 0 && DeploymentActiveAt(*pindexPrev, chainman, Consensus::DEPLOYMENT_CONSENSUSCLEANUP)) {
         if (block.vtx[0]->nLockTime != static_cast<uint32_t>(nHeight - 1)) {
             return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS, "bad-cb-locktime", "block height mismatch in coinbase nLockTime");
         }