HSTS strict transport security header is present in web api response but missing in web response.

I have site where i need to improve the security which is a .net core 6 application. The response header for the site abc.com and for the api is attached. response header for abc.com doesn't have the strict transport security header whereas the api response has the header. I have added both addhsts and usehsts in my program.cs. The frontend is vue and the backend is .net core 6. How to fix this