Sometimes, updates can cause changes in the display settings or they can hide certain folders.
First off, let's try to see if the Junk Mail folder is just hidden. Here's what you can do:
1. Open Outlook and go to the "Mail" view.
2. Scroll down in the navigation pane on the left side.
3. If you see "More," click on it. This should reveal additional folders, and hopefully, your Junk Mail folder is among them.
If you don't find your Junk Mail folder after doing these steps, there's another thing we can try. In Outlook, go to "Preferences," then "General," and uncheck the box for "Hide On My Computer folders." After doing this, check again if the Junk Mail folder is now visible.
References:
1. View or hide folders in Outlook - Microsoft Support
2. Find a message or item with Outlook Search - Microsoft Support