Http request falling into catchError

Question

I am trying to make http request inside httpInterceptor, but always falls in catcherror, is printed on the console the "crashed in err".

  intercept(req: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
    const authToken = localStorage.getItem('token');
    let headers: HttpHeaders = new HttpHeaders();
    headers = headers.append('token', authToken);
    headers = headers.append('Authorization', 'bearer '+authToken);

    if(authToken != null){
        if(req.url !== AppSettings.API_ENDPOINT + 'plano/busca'){
        let http: HttpClient = this.injector.get(HttpClient);

        return http.get('api....', {headers: headers}).pipe(switchMap((response) => {
            console.log('caiu no res')
            console.log(response);
            const newRequest = req.clone({
                setHeaders: { Authorization: `bearer ${authToken}`, token: `${authToken}` }
            });
            return next.handle(newRequest);
        }),
        (err) => {
            console.log('caiu no err');
            if(err instanceof HttpErrorResponse) {
            console.log(err)
            return Observable.throw(err); 
        }}
    )}else {
        return next.handle(req);
        }
    }
}

@Edit:

I tried to make the request inside the service, now I get the request return, but is not cloning the request and adding the header:

intercept(req: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
    const authToken = localStorage.getItem('token');
    let headers: HttpHeaders = new HttpHeaders();
    headers = headers.append('token', authToken);
    headers = headers.append('Authorization', 'bearer '+authToken);

    if(authToken != null){
        if(req.url !== AppSettings.API_ENDPOINT + 'plano/busca'){
        let http: HttpClient = this.injector.get(HttpClient);

        this.authService.validaPlano().subscribe((res) =>{
            console.log(res);
            if(res.data.vencido == true){
                this.authService.Logout();
            }else{
            const newRequest = req.clone({
                setHeaders: { Authorization: `bearer ${authToken}`, token: `${authToken}` }
            });
            return next.handle(newRequest);
            }
        },
        (err) => {
            if(err instanceof HttpErrorResponse) {
            return Observable.throw(err); 
        }
    })
    }else {
        return next.handle(req);
        }
    }
}
}

I already checked and the headers are working correctly, I tested on Postman and the request returns a json sponse... 'Cause it might be falling into the err?