Drive times run with Business Analyst Desktop are showing up in reverse order on reports (eg 15, 10, 5 min rather than 5, 10, 15 min). Rings are appearing in the correct order. This is a problem on both the pre-made and custom reports.
Not sure if you have resolved this issue already but based on your description I would test using Store Setup to create the sf_stores tutorial data located at C:\ArcGIS\Business Analyst\US_2018\Datasets\Tutorial then use the Trade Area wizard to create drive times and then see if running a summary report is still reversing the order.
If this is the case with the tutorial data then I would recommend a repair and/or potentially a full clean uninstall reinstall. If the tutorial data based drive time summary reports are normal then the likely issue has to do with the ID field used on the point feature that the drive times were created on.
Having a good ID field when either using an existing non-Business Analyst created point feature or creating one with Store/Customer Setup is always critical as problem can crop up down stream when using this point feature in other Business Analyst tool. As a best practice I generally always use the option in Store Setup to create a new field (BA_ID) even if I have an existing ID field that I will try to use as when there is an issue there I can easily test selecting the BA_ID field to see if this corrects the issue.