Was this a 'Mist style" kit?
If this is a Winexpert Island Mist kit, or other 'Mist style" kit many of us add sugar to those without any problems. These are designed to be similar to wine coolers. But, many of us like them better with 3 or 4 pounds of sugar added to the primary. I add it to the primary as simple syrup for the mist kits.
This seems to work best if the wine is then aged 6 or 8 months before drinking.
So, when asking questions, it is best to give as much info as possible on the type of kit you are making. That way you will get answers better suited to your needs.
Dave