Oh no! I am sorry this is happening!
Have you tried the new build that we released yesterday Feb 2nd? We had another tester that was having issues with a few items disappearing and we think we have fixed that now because it was tied to having multiple instances of the same plant stand but have never heard of all the items disappearing!
If it isn't fixed in the latest build we would love to get a copy of your save to test.
ok, it sounds like it might be the double instances of the same stand bug coming back. Our main programmer is on a minibreak but will be back next week so hopefully we can get this sorted soon. Thank you so much for letting us know what is going on. One quick question, is the second apartment unlocking for you? That is another bug that just came up today. (Also, feel free to join our discord to share any screen shots of bugs-it's very helpful!)
//Jennevieve