diff --git a/extensions/blockchain-explorer.json b/extensions/blockchain-explorer.json
index 1be1f01..0e3e3fd 100644
--- a/extensions/blockchain-explorer.json
+++ b/extensions/blockchain-explorer.json
@@ -286,7 +286,7 @@
               "    if (!alreadyGeneratedCoins) {",
               "      return false;",
               "    }",
-              "    res.block.alreadyGeneratedCoins = alreadyGeneratedCoins;",
+              "    res.block.alreadyGeneratedCoins = std::to_string(alreadyGeneratedCoins);",
               "",
               "    uint64_t alreadyGeneratedTransactions = m_core.get_blockchain_storage().get_db().get_block_already_generated_transactions(res.block.height);",
               "    if (!alreadyGeneratedTransactions) {",
@@ -603,7 +603,7 @@
               "    uint64_t sizeMedian;",
               "    uint64_t effectiveSizeMedian;",
               "    uint64_t transactionsCumulativeSize;",
-              "    uint64_t alreadyGeneratedCoins;",
+              "    std::string alreadyGeneratedCoins;",
               "    uint64_t alreadyGeneratedTransactions;",
               "    uint64_t baseReward;",
               "    double penalty;",