App Store Application not responding

I hope macjack has some more ideas.

First of all make sure that you have a backup of your files.

I would try removing some .plist files from your Home Folder>Library>Preferences>:

com.apple.appstore.commerce.plist

com.apple.appstored.plist

Move those three to your Desktop, restart your computer, and try to open the App Store.

Next step might be to Reinstall macOS - Apple Support, but before you try that try downloading/installing/running Etrecheck, and post the results on this thread using the steps outlined in: Using EtreCheck - Apple Community

Restart your computer. If that doe's not fix the problem, try using: How to use safe mode on your Mac - Apple Support

macBook_r wrote:

I did try both ways and I still facing the same issue!

Next try to Download/Install macOS Catalina 10.15.4 Combo Update

Try Safari.

Ferd II wrote:

I hope macjack has some more ideas.

Nope, I'm fresh out. Wait... how about Restart? 😜