@Linda1783 I think that for long term rentals, it is important for the host to get in, at least every 2 or 3 weeks, and make sure the place isn't being trashed. So, in future, I would make 'free light cleaning' every X week part of the initial deal you make, so it is known at booking, then you can just work w/them on a convenient time and schedule.
In this case, I would message them again, make it a positive, we offer a free light cleaning for long term guests every XX, please let me know the most convenient time to schedule this....but if they decline the offer, there isn't really anything you can do about it, since there was no original expectation that anyone but the guests would be in the unit. I hope that makes sense.