Cant find Visual Tab / Editor Box for post / page

Hello team,

The visual tab when creating or editing an existing post suddenly disappeared for some reason. The text tab is working and has content in it available to edit but not the visual tab.

All the content is gone (disappeared) and my post is 0, my page is 0 suddenly. All the images are gone too, but when I check in my FTP server /wp-content/uploads/ all the images are actually there, but why it didn’t appear in the IMAGES TAB? Then why I cannot upload any images, it always shows an error like this “an error occured in the upload. please try again”. How to fix this?

I already went through the master list and done the following:
– Changed it to the twentyseventeen theme
– Disabled all plugins
– Did a fresh REinstall of the latest wordpress update
– looked through the forum and attempted some of the “Solved” solutions that were similar to mine but nothing works.

Any help please?