Need help saving .package

Hi all. It's my first time making anything for Sims, and I started with a custom career (lawyer). Everything was working great. It showed up in-game, my Sims were getting the promotions like they should, their requirements for getting the next promotion showed up, etc.

Except when I went to tweak one tiny little thing, I suddenly got an error when I went to save, and it won't go away.


The Sims 4 Studio - Version 3.0.1.8

System.NullReferenceException: Object reference not set to an instance of an object.

at S4Studio.Data.IO.Tuning.SimDataResource.GenerateRowData(List`1 tables, XElement xtable, IList`1 schemas) in C:\Sims\Studio\S4S\TheS4Studio\S4Studio.Shared\IO\Tuning\SimData\SimDataResource.cs:line 608

at S4Studio.Data.IO.Tuning.SimDataResource.Write(Stream stream, IReferenceList resources) in C:\Sims\Studio\S4S\TheS4Studio\S4Studio.Shared\IO\Tuning\SimData\SimDataResource.cs:line 48

at S4Studio.Data.IO.Package.DBPFPackage.WriteResourceStream(FileStream final_stream, IPackedResource resource, IDBPFResourcePointer index) in C:\Sims\Studio\S4S\TheS4Studio\S4Studio.Shared\IO\Package\DBPFPackage.cs:line 553

at S4Studio.Data.IO.Package.DBPFPackage.WriteDataStream(Stream src_stream, FileStream final_stream) in C:\Sims\Studio\S4S\TheS4Studio\S4Studio.Shared\IO\Package\DBPFPackage.cs:line 522

at S4Studio.Data.IO.Package.DBPFPackage.SaveTempPackage(String out_file, String tmp, Stream pkg_stream) in C:\Sims\Studio\S4S\TheS4Studio\S4Studio.Shared\IO\Package\DBPFPackage.cs:line 457

at S4Studio.Data.IO.Package.DBPFPackage.Save(String out_file, Boolean inline, String temp_path) in C:\Sims\Studio\S4S\TheS4Studio\S4Studio.Shared\IO\Package\DBPFPackage.cs:line 384

at S4Studio.Shared.StudioDocumentModel.Save(String filename) in C:\Sims\Studio\S4S\TheS4Studio\S4Studio.Shared\ViewModels\App\StudioDocumentModel.cs:line 254


I'm not sure why this is happening. I didn't mess with any of the Sims 4 Studio files, only the ones inside my .package. It was working just fine before.

If anybody could help me with this, I'd really appreciate it. I'm very new to modding and not too great with coding and such. And I apologize if it's something simple that I overlooked. It's quite late and I've been having nightmares for the last few nights, so I'm tired.