Save error

My sister and I spent about six hours building a business-residential lot in the new Nordhaven world. Right when we finished building we tried to save the game, but it just sat loading for several minutes. We then tried to save the lot to the gallery so that we wouldn't lose our progress, but we got an error message every time. Our final attempt to salvage our build was to go back into live mode and save from there, but once again the game just sat loading for several minutes, and on top of that our game wouldn't unpause even if we manually clicked the play button. We ended up having to close the entire game, and upon starting it up again we discovered that all of our progress we made over the past six hours had been lost. This is absolutely unacceptable; we are both incredibly disappointed and frustrated that our time has been wasted. This save error/glitch needs to be patched as soon as possible, but in the meantime, if there is any workaround to this please let me know. We were playing on a Playstation 4 console.