Angular - JWT Refresh Token

After a long time I didn't find an approach about refresing tokens TTL: 30 minutes Refresh TTL: 2 Weeks

If I refresh the page after 45 minutes innactive then I make a getAccessToken() function to send the expired token and then send me back a refreshed token. The big problem is that if my page makes more than 1 ajax request then if the first request invalidate my token the second request force my to relogin becauce it send empty token

@NgModule({
providers: [
    {
        provide: AuthHttp,
        useFactory: authHttpServiceFactory,
        deps: [Http, RequestOptions, Router]
    }
]
})

export function authHttpServiceFactory(http: Http, options: RequestOptions, router: Router) {
return new AuthHttp(new AuthConfig({
    tokenName: 'token',
    tokenGetter: (() => getAccessToken(http,router)),
    //tokenGetter: (() => localStorage.getItem('JWToken')),
    globalHeaders: [{'Content-Type': 'application/json'}],
    noJwtError: true,
}), http, options);
}


function getAccessToken(http: Http, router:Router): Promise<string> {

let jwtHelper: JwtHelper = new JwtHelper();

let accessToken = localStorage.getItem('JWToken');

if( accessToken == '' || !accessToken || accessToken == undefined || accessToken == null){
    router.navigate(['./admin/login']);
    return;
}


if (jwtHelper.isTokenExpired(accessToken)) {
    return new Promise((resolve, reject) => {
        let refreshTokenService: RefreshTokenService = new RefreshTokenService(http);
        refreshTokenService.refreshToken(accessToken).subscribe((res: any) => {
            res = res.json();

            if(res.token) {
                localStorage.setItem('JWToken', res.token);
                resolve(res.token);

            }else{
                localStorage.removeItem('JWToken');

                router.navigate(['./admin/login']);
            }
        });
    });
} else {
    return Promise.resolve(accessToken);
}
}

I want the requests wait for the response of the first request