Hi Bev5,
I am pleased to report that we have just made an adjustment to our site intended to correct this issue, so you should now be able to successfully remove the Subtitle from any of your items you are relisting using the Edit and Relist option on your Closed Listings page moving forward.
If you notice any remaining issues of this nature, please don't hesitate to let us know. Thanks again for helping to bring this to our attention.
-Mike