Post content suddenly not showing

I’ve just recently noticed that some of my posts are displaying no content at all. The text appears within the editor but not live. This only appears to affect older posts.

I’ve tried deactivating all plugins and updating the posts but nothing appears still. I’ve also checked the cache of the posts and on the last cache on 25th October the content is still there. I have not installed any new plugins in that time nor have I done any editing of the theme or database.

Does anyone have any idea why this may be happening?

Thanks.

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