I just checked their website
http://luckyfish.io/ and I saw the statement that they are going to stop deposits after 30th November. It doesn't mean they necessarily closing the business permanently though. Maybe they are going through some kind of maintenance. Why are they closing? Do you have any further information about their issues? Maybe it is a legal problem which they don't want to disclose.
Most probably because of the unsold issues about this site that hurt their reputation and yeah many the regulations as well. They still not release a statement with this one, the deposit will be stop and the withdrawal will be open until all the players got their funds hopefully no more problems on withdrawing your money.
as long they wont really be releasing any announcement regarding on this then we would really be just ending up on having these speculation
but those possible reasons could neither on those things been mentioned above neither on some issues or regulatory or simply not really
feasible at all thats why they had these kind of stop or pause but who knows if this is already the end.