Chrome stops Recaptcha v3 from sending site key to back-end?

Question

I'm trying to add recaptcha v3 to my express app. I tried this code:

https://github.com/Leog004/RecaptchaV3-NodeJS

read this post but it did not help:

SameSite warning Chrome 77

this is what chrome says:

Because a cookie’s SameSite attribute was not set or is invalid, it defaults to SameSite=Lax, which prevents the cookie from being sent in a cross-site request. This behavior protects user data from accidentally leaking to third parties and cross-site request forgery. Resolve this issue by updating the attributes of the cookie: Specify SameSite=None and Secure if the cookie should be sent in cross-site requests. This enables third-party use. Specify SameSite=Strict or SameSite=Lax if the cookie should not be sent in cross-site requests.

This is my session configuration for saving sessions to mongodb: (I use it as app.use(session(sessionconf)) for every request in back-end)

 const sessionconf = {
            store: MongodbStore.create({
                mongoUrl: str,
                secret,
                touchAfter: 24 * 60 * 60
            }),
            secret,
            resave: false,
            name: '_cloud',
            saveUninitialized: false
            ,
            cookie: {
                httpOnly: true, 
                secure: true,
                expires: Date.now() + 1000 * 60 * 60 * 1 ,
                maxAge: 1000 * 60 * 60 * 1
            }
        }

everything looks working but when fetching the post route from the front-end, the body of post request in the back-end, shows {}