Modal container div to scroll

[miriamramos]

I'm submitting a...

[ ] Regression (a behavior that used to work and stopped working in a new release)
[x] Bug report  
[ ] Feature request
[ ] Documentation issue or request

Current behavior

I have a page that has a scroll and this page open a modal, in this modal I have a div that contains a scroll that I target and put in a container, but this not working, if I remove the container tag the backgroud page scroll but I need the div that is inside the modal.

Minimal reproduction of the problem with instructions

In my ngOnInit() function

const config: ScrollToConfigOptions = {
container: 'custom-container',
target: 'scrollar',
offset: 200
};
this._scrollToService.scrollTo(config);

In my html

aroud a custom-container div
<div [ngSwitch]="view" style="overflow-y: scroll;height: 640px;" id="scrollar">

Environment

Angular version: 5.1.0

Your version of `@nicky-lenaers/ngx-scroll-to`:
^0.6.1

Browser:
- [x] Chrome (desktop) version XX
- [ ] Chrome (Android) version XX
- [ ] Chrome (iOS) version XX
- [ ] Firefox version XX
- [ ] Safari (desktop) version XX
- [ ] Safari (iOS) version XX
- [ ] IE version XX
- [ ] Edge version XX
 
For Tooling issues:
- Node version: 6.1.0
- Platform:  Windows