Hi, I'm currently doing a simulation of tensile testing on a dumbbell model, I've applied split line on both the grip area of the model. One of the side is fixed, while the other side is applied with a prescribed displacement. However, I encounter a problem where the split line area has a high stress (attached pic). May I know how to resolve this issue? Thanks.

Edu ​​​​​​​SOLIDWORKS ​​​​​​​Simulation ​​​​​​​