+ icon to create Case in App Studio preview is not showing

Hello all,
I am in middle of my exam and suddenly from the cloud instance the + icon to create case from preview screen is gone. Nothing has changed regarding access or portal configuration ,it was working fine all this while. Suddenly its gone, gone from end user portals too.
Saved my application rule, the OOTB Work portal rule by removing & re-adding the case types . logout and login, but nothing helped.

I ran network trace while clicking preview , and could find only this datapge to be failed. however on standalone run in dev studio it fetched the case types correctly.

Could someone please help urgently . this is a blocker for testing & also finishing on time.

@MayukhG17734438 It is strange that “+” suddently disappeared. If your goal is to launch a new case, you can use ‘Quick create’ widget as an alternative so that you can continue your testing.

  1. Add the Quick create widget to a landing page.

  1. Add your case type to create in the widget setting.

  1. At runtime, click the quick create link to lauch a new case.

Sorry, not sure why the + Create button disappeared. As an alternative, you can use DX APIs for case creation to move forward or @Will_Cho recommendations.