handling incorrect captcha and check not found cases

exceptions/ofdrequestexception.h

@@ -0,0 +1,16 @@
+#ifndef OFDREQUESTEXCEPTION_H
+#define OFDREQUESTEXCEPTION_H
+
+#include <exception>
+#include <string>
+
+class OfdRequestException : public std::exception
+{
+private:
+    std::string message;
+public:
+    OfdRequestException(const char* msg);
+    const char* what() throw();
+};
+
+#endif // OFDREQUESTEXCEPTION_H