Revision Mid Cheek Lift

I had a mini cheek lift October 9, 2017 along with fat transfer on the cheeks and jowls. I also had a chin lift All was looking good until 2 months later when I noticed the jowls came back. The Dr. said during one of my check ups, that this is normal as we make expressions with our face and mouth. I don't feel he is telling me the truth. I think either my skin stretched, he did not pulled enough to make up for stretching of the skin and compensate for the fat that was lost in the jowls when the fat was injected. I mentioned this during other visits but she basicall tells me the same thing. He acknowledged that the fat injection in the jowls did not stay and I asked him if he could reinject. He said no as it will look uneven. Is the Dr telling the truth that facial expressions can cause these lines on the jowls to come back?