WSUS server has a maximum size limit and sometimes the update package may exceed the size limit if you try something drastic such as publishing the entire MS Office in a custom package through SVM. You shouldn't do that in general. This article will help you tackle such problems and achieve advanced setup.
Update can't be published to the WSUS server due to the locally published packages size limit.
The WSUS package size limit is 382 MB by default.
Login to your WSUS server and then run the Powershell console as an administrator. Run the below commands one by one to change the locally published package size limit to 1024 MB.