I apologize if this is posted in the wrong place, but I need an URGENT HELP!
I was building a map and to reduce lag I unioned several parts (of the same materials and of the same models). But when I checked it out after some time they all disappeared . I cant undo it as well as I left the studio after performing the union operation…
I searched the devforum and found several similar posts but none of them had any solution or not even any other alternatives.
Is there any solution to it… I literally just wasted a lot of my time
I believe I found a post before but I cannot find it now, I believe it states that these are corrupted unions and cannot be recovered unfortunately. But there is a goodside now you can remake the map with experience and make it even better than it was before!
Corrupted unions and invisible has always been a roblox studio bug since god knows when. If you have your autosave on, you could always recover it. In my case when i’m team building, whenever someone is unioning and went missing, close and open the studio will be enough to be present again. The union is there, just invisible
The union is still there, I normally reset studio and it fixes it. Don’t worry it’s not gone, unless your situation is different because I can hover over my union and it’s still there.
If you make a complex object with a lot of unions it can disappear for some reason. Just try splitting up the object or try positioning the part to be a more simple union before unioning it.
As far as I am aware there is no solution to this, this has happened because the union has corrupted and does not save properly. this is an incredibly annoying bug and as a result your work is probably lost. Sometimes if you separate the union (it should still register as a union being there but it wont be visible) it will show the parts and you can union it again but this only works some of the time
Don’t worry, nothing’s wrong. This happened to me many times before. Simply save the unions, exit ROBLOX Studio and reload. If that doesn’t work then your unions may need a few moments to load-in. Otherwise, nothing is wrong.
Well, this can be due to two reasons (normally) firstly because of union corruption, which is whenever you make a very complex union or a union that takes up too much memory or it can be a client side bug, which is okay, the only thing that happenes whenver this bug appears is that the union won’t be visible in your client, instead whenever playing the game or another person entering studio they will be able to see it.
If it took you that much time to do I highly suggest take a backup of how your place is then
Go on Roblox find the place and go on the Configure Start Place
Then Go to Version History and retrieve the version History of the day that you new that the union was still there and not corrupted (if you mess this up you would have the back up just in case)
But there is a goodside now you can remake the map with experience and make it even better than it was before! 
