Weird WordPress Problem

Hello,
I had a really word wordpress problem recently and I’m completely lost. I’m a freelancer and my client made me an administrator to a ww.wp.xz.cn site he wanted me to create. So I get him to set it up with hosting and I was building the site without any problems. I was able to add plugins and change categories, add users, etc. About a week ago I lost those abilities and I don’t know why or what I can do about getting them back. It’s a very barebones wordpress backend. All I can do is create posts and I can still edit with elementor. I don’t know what to do and I don’t understand how this happened. Can someone please help me.
Dan

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