IL vehicle registration transfer

I purchased a vehicle a couple weeks ago on Jan 17th at a dealership in Wisconsin. i live in Illinois. I traded in my old vehicle & transferred the plates from the car i traded in, onto my new one. How long until the registration transfer is complete on the DMV’s end? I went on ilsos.gov to check on my title and registration status and it says “the information could not be processed at this time”. But if i put in a different vehicle VIN, it works. Any thoughts on what it could be or how long it takes for the transfer? Thanks.