Hello Wayne,
That is because of reason 3. Remember eBay is more stringent with bids placed from computers that are not yours. The solution is to change your eBay password at the eBay site to be slightly more stringent, and then update it at our site. This happens for about 1% of users; this suggestion always solves the problem.
Snipe services are not allowed to use the eBay API otherwise this would be bulletproof, but we all experience this.
Take care,
BidSlammer Customer Care
Guest