diff --git a/trie/zk_trie_database.go b/trie/zk_trie_database.go
index 0bf7647d0fc7..448427cd709a 100644
--- a/trie/zk_trie_database.go
+++ b/trie/zk_trie_database.go
@@ -66,10 +66,8 @@ func (l *ZktrieDatabase) Get(key []byte) ([]byte, error) {
 func (l *ZktrieDatabase) UpdatePreimage(preimage []byte, hashField *big.Int) {
 	db := l.db
 	if db.preimages != nil { // Ugly direct check but avoids the below write lock
-		db.lock.Lock()
 		// we must copy the input key
 		db.preimages.insertPreimage(map[common.Hash][]byte{common.BytesToHash(hashField.Bytes()): common.CopyBytes(preimage)})
-		db.lock.Unlock()
 	}
 }