InvalidValueError: in property origins: not an Array - multiple google maps APIs

I am trying to use google.maps.DistanceMatrixService() with some other services (google.maps.LatLng, google.maps.DirectionsService) and I get this error

js?key=MYKEY:35 InvalidValueError: in property origins: not an Array

Stack trace ends at distance_matrix.js:1 if that helps.

Code works without problems until I add part with distance matrix. My intuition was that it wants multiple keys for multiple APIs in form of array, but I am probably wrong (sorry I am a beginner in javascript). I tried to do some research but I was unable to find anything about this error. I tried creating key for distances matrix, using multiple keys, I also used string values for origins/destination to make sure the error is not here. But nothing worked.

This is my code:

var distanceService = new google.maps.DistanceMatrixService();
         distanceService.getDistanceMatrix({
            origins: jams[i].getCenter(),
            destinations: coordinates,
            unitSystem: google.maps.UnitSystem.METRIC,
            durationInTraffic: true
        },
        function (response, status) {
            if (status !== google.maps.DistanceMatrixStatus.OK) {
                console.log('Error:', status);
            } else {
                console.log(response);
                $("#distance").text(response.rows[0].elements[0].distance.text).show();
                $("#duration").text(response.rows[0].elements[0].duration.text).show();
            }
        });

Here is also the code for loading libraries and API key (this part was not written by me):

  <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.3/jquery.min.js"></script>
<script type="text/javascript" src="https://maps.googleapis.com/maps/api/js?key=MYKEY"></script>
<script src="https://cdn.rawgit.com/googlemaps/v3-utility-library/infobox/1.1.13/src/infobox.js
"></script>

via Kanter