Expression transformation acquisition failed in 4.26

[salier]

I used the 4.26 unreal engine to build the augmented faces successfully, but failed to show the fox and mask. I successfully tried to print the transformation of the model. But when I wanted to print the weight of different expressions, it didn't work properly. The numbers printed out were all 0 (and failed)

[salier]

The debug interface displays normally. It works normally at the same time. The transformation of three points is also normal
It is unable to get the value of mixed shape. And it returns failure

[salier]

There is a flash back. The output log display plug-in disappears

[salier]