Duplicating listings randomly and not listing other items

I’m having a concurrent issue. Using GS 666.

There is a problem every time I list which when I post via the Batch process. GS will list most items
but seemingly get up hung up on a handful , which either get ignored (is red) in uploading or it uploads but
appears with a ! mark beside it (sometimes) and then I will re-upload them then the Ebay server will
reject some of them as oddly some of them will have listed fine but does not show up properly on
GS , and some of them I have to try several times to get them listed properly. My main concern is the ones that
appear not to be listed but are. That’s when I Get a kick back from Ebay saying "duplicate item removal’…which thankfully does not affect my account in a negative way. Please explain a solution and CAUSE.

GarageSale 6.6.6 was released almost 3 years ago. Please see if this bug is still present in either GarageSale 6.9.x or 7 the 7 beta series.