diff --git a/src/core/atomicdex/api/kdf/rpc_v2/rpc2.enable_erc20.hpp b/src/core/atomicdex/api/kdf/rpc_v2/rpc2.enable_erc20.hpp
index 26452f9593..a849f9638f 100644
--- a/src/core/atomicdex/api/kdf/rpc_v2/rpc2.enable_erc20.hpp
+++ b/src/core/atomicdex/api/kdf/rpc_v2/rpc2.enable_erc20.hpp
@@ -16,6 +16,7 @@
 
 #pragma once
 
+#include <optional>
 #include <string>
 
 #include <nlohmann/json_fwd.hpp> //> nlohmann::json
@@ -56,4 +57,4 @@ namespace atomic_dex::kdf
 
     void to_json(nlohmann::json& j, const enable_erc20_rpc_request& request);
     void from_json(const nlohmann::json& j, enable_erc20_rpc_result& in);
-}
\ No newline at end of file
+}