dallas_grant, you can blame eBay - notorious for their tech "glitches" - and possibly PayPal (if it's PayPal that's the issue, rather than eBay's implementation of the payment page)... but not the sellers.
Really, serioiusly, think about what you are saying! You cannot honestly want the seller to be on tap 24 hours of every day of the week. Those would be slave conditions!
If the sellers are professional businesses, then it's more than likely they have regular business hours. If you contact a seller outside of business hours (and such may be the case if you've bought from overseas sellers), the response is going to be something like "We're out of the office" or "You've contacted us outside of business hours". They might be not just out of the office, but driving home, or spending valuable time with the kids, or eating, or sleeping.
If the sellers are hobby sellers, it would be a fast road to mental burnout if they were available at all hours. They, too, must take time out to relax and de-stress and do other things.
Sometimes sellers will be on holidays. If the seller concerned doesn't have a store, I understand that they don't have access to "holiday settings". Instead, such sellers may opt to extend their handling time to take account of their holiday period.
Sometimes sellers are ill. Sometimes sellers have family members who are ill, or there may be a bereavement in the family. All of these things happen, and there's no point in declaring "if you can't take orders don't have the ability to order stuff".
I understand it's annoying when you find that you've paid for two lots of items through a technical error which isn't your fault. Hopefully it won't take long before it can be resolved for you. If you contact sellers politely to explain what's happened, and ask them to cancel the second order in each case, you will almost certainly get a good result.
Best of luck.
