After adding change in the process model, the form unexpected closed after clicking the save button

Hi community members,

Because of a new feature, I added a xor gate and a new path in a process model. The form is some where after the XOR gate and new path. The issue is now when I clicking the save button, the form unexpected closed (no error message). The previous correct behavior is clicking save button and then clicking submit button, which means the form is stay open after clicking save and before clicking submit. Now I have to go to the process model and click the form node to view the form again then click submit. I didn't change anything in interface/UI. What the possible cause for this issue and any suggestions?

Thanks!