All the US holdings are joint with my wife but still had to fill out a form for both of us as it doesn't automatically file one for my spouse. I filed mine successfully but when I went to Netfile my wife's form, I also got a reject code 484 saying it had already been filed. I checked the acknowledgment report and I do have a confirmation code for my wife's also. The only thing I can see is it got filed at the same time as mine even though you are asked to file them separately the same way you file the income tax return. Hope this can help others in the future
