Internal server error 500 when calling service

I created a model and a query model to store information in the database. I use the call below to query these items and when I try to make a call to it through the browser I get a 500 internal server error.

IRepositoryItemService repoService = getService(IRepositoryItemService.class);

        IQueryService queryService = getService(IQueryService.class);



        PersistentVoteItemQueryModel queryModel = BasePersistentVoteItemQueryModel.PersistentVoteItemQueryModel.ROOT;

        IItemQuery itemQuery = IItemQuery.FACTORY.newInstance(queryModel);

       

        //itemQuery.filter(queryModel.WorkitemID()._eq(UUID.valueOf(uuid)));

       

        IItemQueryPage itemQueryPage = queryService.queryItems(itemQuery,

                IQueryService.EMPTY_PARAMETERS,

                IQueryService.ITEM_QUERY_MAX_PAGE_SIZE);



        IItem[] items = repoService.fetchItems(itemQueryPage

                .handlesAsArray(), null);

        ArrayList<PersistentVoteItem> voteItems = new ArrayList<PersistentVoteItem>();

        for (IItem item : items){

            if (item instanceof PersistentVoteItem)

                voteItems.add((PersistentVoteItem)item);

        }

       

        return (PersistentVoteItem) voteItems.get(0);

The model is simple, it inherits auditable. Contains a string field (that isn't queryable) and a UUID field that is queryable. Is there a common reason why this would throw an internal server error? Also I checked the server logs and didn't see an error. Is there a way I can get the server to tell me what this 500 error is? Thanks in advance.