Mix the softened cream cheese and the milk together in a medium mixing bowl using a whisk. Try to combine the two together as much as possible. There will likely still be some small chunks of cream cheese, but that's ok as long as they are small.
Add the lemonade and mix together well.
Pour the mixture into a Ninja Creami pint container, add the blueberries and freeze on a level surface in a cold freezer for a full 24 hours.
After 24 hours, remove the pint from the freezer. Remove the lid.
Place the Ninja Creami pint into the outer bowl. Place the outer bowl with the pint in it, into the Ninja Creami machine and turn until the outer bowl locks into place. Push the SORBET button. During the SORBET function, the sorbet will mix together and become very creamy. This should take approximately 2 minutes.
Once the SORBET function has ended, turn the outer bowl and release it from the Ninja Creami machine.
Your sorbet is ready to eat! Enjoy!
*** If the sorbet is not quite creamy enough, place the outer bowl with the pint back into the Ninja Creami machine and lock it into place. Choose the RE-SPIN function. Once the Ninja Creami completes the RE-SPIN cycle, remove the outer bowl from the machine.