Allowed one edit before being locked out

I have been added as an Admin to a WordPress blog and have recently experienced several problems. Whereas before I could save/ edit a post several times before submitting it for review, now I am only allowed to save once.

After hitting save, the page begins refreshing before going entirely white. The post then appears in the dashboard’s list of All Posts, yet does not allow me to edit. When I click on the post’s title to do so, once again it takes me to a white screen.

Oddly enough, I am able to add a new post, upload photos etc. just fine. The problem is specific to saving a post and editing a previously saved post.

Can someone please offer insights or solutions to this frustrating problem?

Thanks so much!

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