I am sorry to hear that you have encountered difficulty posting listings, we are not aware of any issues that would cause this to occur. It is possible that eBay's API rejected your listings for some issue within them - if this is the case, you can check your notifications by clicking on the red box in the upper right of your account pages (it should have a number in it) to see failure notifications.
If you do not have such notifications or you are unsure about the error message from such a message, please file a support case from under the Help tab of the site letting us know the details of what you are experiencing and we'll be happy to look into it for you.
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