Custom metahuman weird mouth shapes

[nayarharik]

Hi

I made a metahuman with the metahuman identity using the conventional video to metahuman method using the metahuman animator pluggin, which is shown on the left side(giving decent mouth shapes).
Then I used these codes to make my custom metahuman with my scanned model, which is shown on the right. but I am getting weird mouth shapes. Is this solvable.

PFA the image for reference

Regards