Can't Select Text using a selection tool

You may have accidentally activated Hide Edges 

Try hitting (cmd/ctrl+ H),

I have a solution for you .Check if it wokrs or not..

Open AI and then >> Edit >> Preferrence>>Selection And Anchor Display >> Object Selection By path only(Make sure it is Unchecked)

I'm having the same issue but it comes and goes. It's very strange. And it's not just this issue. Other issues occurring at the same time like the menu buttons don't display all the different options in the pop out.

Any update on this?

have you tried holding the Ctrl key down while left-clicking on the text, its another way to access the text and type in more

When you reset the preferences did you restart before starting the application? Clearing the system cache for preferences might help. But let's see if it is a user issue. Can you start your system under another user? If the problem persists then it is not the user preferences. You might need to uninstall/reinstall the applciation and if all else fails use the Adobe cleaner.

Have you updated your system software? Another question is have you added any third party products or used any beta software? These all can create havoc on the system. I once used beta technology and we had to reinstall my entire system since it messed up all Adobe and Apple video apps.

Here is the link for the Adobe Cleaner but I would try the software on the same system under another user so you can see if you need to take drastic measures.

https://helpx.adobe.com/creative-cloud/kb/cc-cleaner-tool-installation-problems.html

Reset your preferences and try again.

How to set preferences in Illustrator