You should remove the nest box as soon as the first clutch are no longer using the nest box, and since you didn’t, the result is that the pair have now double clutched.
Before you breed, you really need to know what you will do with the babies, whether you have homes lined up (which is the most ideal thing to do), or are going to keep them... since you can’t keep them due to not having the room, and will get into trouble if the management finds out, your only option is to obviously find them new homes (of course the babies from this second clutch can’t go yet). The babies from the first clutch, are they fully weaned yet? Had you been planning to keep them or find them homes?