What is the purpose of the cookie named 'session' in Flask?

I am using flask to set JWT token as cookie. I named it jwt_token in the browser. However, whenever I login, when the jwt_tokencookie is set, another cookie named session is being set in the respond from the server together with the jwt_token. The session cookie is causing the warning

"A cookie associated with a cross-site resource at http://testing.com:8080/ was set without the SameSite attribute. It has been blocked, as Chrome now only delivers cookies with cross-site requests if they are set with SameSite=None and Secure. You can review cookies in developer tools under Application>Storage>Cookies and see more details at https://www.chromestatus.com/feature/5088147346030592 and https://www.chromestatus.com/feature/5633521622188032. "

I believed that it is caused by the cookie named session does not have the samesite & secured attributes. How do i solve this issue?