ImGui partial Demo Window showing

I am getting a weird output with this code when compiling with OpenGL (#version 150).

if (!GLFW_initialized) {

            int success = glfwInit();

            /* code required for macOS to run with ImGui:: */
            glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
            glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
            glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
            #ifdef __APPLE__
             glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE);
            #endif

            /* end of APPLE code */

            HELIX_CORE_ASSERT(success, "GLFW failed to initialize");

            glfwSetErrorCallback([] (int _error, const char* _description) {

                HELIX_CORE_ERROR("GLFW Error [{0}]: {1}", _error, _description);

            });

            GLFW_initialized = true;

        }

The image below shows what I am getting. The Demo Window is not showing up as it should (from the research I have done). This part of an engine I am writing and the black window is generated using GLFW (3.3.2). Any help with this would be much appreciated!