Post Grid fails to load more or show next page

I am user with an expert license. I am using the post grid to show the custom posts (called Restoration), it can show only the first page (ie 9 items), whenever I click load more button, it is loading forever, and I can see from chrome console there is error, Failed to load resource: the server responded with a status of 404 () . Please help to solve the issue, thanks in advance.

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