Windows 10 Flipping Contacts Names in Outlook.com

I have an Outlook.com email address connected to Outlook 2013 on 2 PCs. One PC has Windows 8.1, the other has Windows 10. Outlook on the Windows 10 machine shows some contacts' names flipped around (last name as first, first as last); when I try to correct them on Outlook, it messes them up on Outlook.com. This doesn't happen with the Windows 8.1 machine. Obviously, the MS people broke something in Win 10 that was working in Win 8.1. Please fix, or give me some ideas about how I can resolve this. Until that happens, I'll be using the 8.1 machine.

In Outlook select File>Options>People

Under Names and filing, check the setting for the order the name is to appear as. Maybe that might be the issue?

My contacts show up fine on both Windows 10 (PC and Surface Pro 2), Outlook.com and Android phone synced to it. All my contacts are displayed properly. But I am not using an outlook.com email address (my isp email address is tied to the account).

No, when I change around the names in the Outlook client address book so that they are correct, the names are flipped around in Outlook.com. If I correct them in Outlook.com, they're flipped around in the Outlook client address book. This only happens with the Outlook client on my Win 10 PC; it's fine on the Outlook client on my Win 8.1 machine.