Did you back up before updating?
Can you restore to a previous back-up? it looks like you broke the javascript somehow. You aren’t using any legacy add-ons with your site by any chance?
Some known issues if you manually updated instead of auto update. See posts here
Premier should be on 4.9.17
Is the CSV file in your media library?Imports are a 3-step process.
1) The file is uploaded to the WP Media Library.
2) A background process reads the CSV into the locations list. It may run this process multiple times on slow servers or with lists over 2500 locations.
Starting another one just slows it down more and if your server cant handle it or if Google is deprecating your site it could stop in its tracks.