Invalid source table in Table Operator TTL

This statement:

```
SELECT
PULocationID, DOLocationID,
pu_zones.Zone as PULocationName,
do_zones.Zone as DOLocationName,
AVG(fare_amount) as avg_amount
INTO avg_fares
FROM TTL(TUMBLE(trips, tpep_pickup_datetime, '1 HOUR'), window_end, '1 HOUR')
INNER JOIN zones pu_zones ON trips.PULocationID = pu_zones.LocationID
INNER JOIN zones do_zones ON trips.DOLocationID = do_zones.LocationID
WHERE PULocationID = 123
GROUP BY PULocationID, DOLocationID;
```

generates the above error