React Router V7 + Better Auth (Plugin OpenAPI)

Hi! I have some question about plugin openAPI. Now I make a game with cocos creator use Typescript and I use React Router V7 for API and web admin page. And I try to fetch get session in my game but i show error "blocked by CORS policy" so now I have no idea what to do next. (I already add "credentials: 'include'" in fetch) (and I also try to create middleware to add CORS headers but it didn't work)