Hi there, richard96.
I tried to export the VAT Detail report to PDF and the columns are showing fine. There are several factors that may contribute to alignment issues in the columns when exporting reports from QBO. I'll share the steps that can resolve these.
First, clear your cache or temporary internet files. Here's an article as a guide: Clear Cache and Cookies to Fix Issues When Using QuickBooks Online.
Second, outdated versions of Adobe might not work properly when printing or exporting documents. To check which version you're using on a Windows computer, go to the Start menu, then go to Programs & Features. This menu will display which version of Acrobat or Reader you're using. The latest versions of Adobe can be located on the Adobe website
Once done, go back to the report and export it again.
Feel free to check out this article in case you will need them when running reports in QBO:
Don't hesitate to reply to let me know if you anything from us. I'd be glad to get back here and offer my help to you again.