Have had this problem multiple times, last time today. The problem disappears after game restart but pops up again sometimes.
@Sozki Can I confirm a few things in your case?
Mods/CC or Repair information: (please click spoiler tag):
Do you have Mods or CC (or have you ever had them)? If you do please remove them in this process and try the troubleshooting as described below. (If you don't have Mods or CC, just skip the part about removing the Mods folder, but still delete the cache files mentioned and run the repair.) If you ever had Mods or CC in the past then do the steps as if you have them currently (removing the Mods folder), as there could be damage that has remained after you removed them.
Do not re-add any or your Mods or CC at this time. Please then restart your game and do not enter your previous game-save but begin a new game. See if the issue is present in this new game-save.
If it was Mods/CC: If this fixes the issue I would recommend that you check with the Mod and CC creators to see if there are any known issues with their Mod/CC clashing with the recent update and if so do they have an updated Mod/CC that will address the changes in the game's code from the update. You can then re-add your updated Mods/CC one at a time to see if one was conflicting with the function/causing the glitch - but do not re-add the old config file from the old mods folder, as it is possible for it to have become corrupted also.
Let us know how it goes. Thanks!
@SheriGRHi!
I'm playing on PC and own almost every pack, I only lack couple of Stuff packs (I don't own My First Pet, Romantic Garden and Perfect Patio).
Game version 1.60.54.1020
It has happened on multiple worlds previously, I really can't remember which all. The Honeydew lot in University at least. The latest one (yesterday) happened in Brindleton Bay on the left bottom corner lot. I can't remember if it once had a building on it (I put a pic of the lot, because I renamed it and am playing in Finnish so pic helps more I think), but right now I was building from scratch. If it happens again soon I'll screenshot something for you but right now I have none.
I had problems previously with that Honeydew lot also, not able to remove or build walls etc (and I have no idea what that "conflicting block cluster" means because as I said my game is in Finnish so ^^' ). But I had no error messages or anything this time, it just didn't recognize the walls when I tried to place wallpapers or use select tool to use the same wallpaper. Before restarting I didn't try removing walls so I can't say for sure if I had gotten a error message if I tried.
I haven't used mods for a looooong time, but I'll remove the cache files and use repair anyway just to be sure. If the problem reoccurs I'll be sure to tell.
@Sozki Thank you for your information and screenshot! I'm glad you're going to try clearing the cache per the directions. Sometimes this can cause issues related to a broken Mod/CC even after the offending Mod/CC has been removed. Doing the game repair afterward should also give your game files a good check and repair if needed, in case anything in them has become glitchy or corrupted. That's a great place to begin troubleshooting.
If the issue does reoccur please do try to capture screenshots, as this often helps a great deal. If it happens on a particular lot you could also save and upload the lot to the gallery with a name something like 'Glitch Test', and let me know it's there, and I could test it in my game in the same lot. (Please include what world and lot it was placed in and your gallery name if it's different than on AHQ.)
I look forward to updates. Hopefully it will be good news that clearing the cache files and doing the repair fixed the issue. If not, we can try a game reset &/or the above lot share via the gallery.
