Smart object issue
Hello everyone.
I have been dealing with Adobe Photoshop CC for years and with it's smart object.
I used to make in the smart object more than a 10 layers maybe more.
Recently i have been facing an issue, every time i save it gives me message stating "
Can't save this document back to its original format.
Flatten layers and discard extra data as necessary and choose
File > Save again."
Yep i flatted the layers and it worked but what is the use of the smart object So ?
I tried to place embedded and still the same, same goes with Linked.
I need help please.
P.s: this went with other CC and CS.
P.s: tried the update all modified content.

PS:Thus this the issue am facing.
Thanks.
