I am using Next.js 15 and React 19. To implement ISR, I used the following code: export const dynamic = "force-static"; and export const revalidate = 5184000;. When the ISR writes exceeded 8 million, I commented out export const dynamic = "force-static"; and redeployed my project. However, this caused all previously generated ISR pages to disappear, meaning I paid for writes unnecessarily. How can I resolve this issue? I only want to use the free 2 million writes per month. My total pages exceed 50 million. What can I do to handle this situation? I urgently need help.