Its not unusual for coffee machines to jam up from lack of use. Sometimes its dried coffee which sets like concrete in the shutes and guides inside the machine, other times its from lime build-up from the water. Try doing a clean function and see if that frees things up. You may have to purchase a descaler tablet. Check the owners manual on how to do a descale / clean as it can be a different method on other brands and models.

Remember...when a unit sits the interior lining of the hot water reservoir tends to dry and debris falls to the floor. If you Purged the Brewer as per page 9 of the manual you would not have this problem. Pg 12 refers to DE-Scaling, which you must do now. Always use Distilled Water to prevent mineral build up.