As a seller why is my largest $1000+ "Seller Protection - Not Eligible"

[dunderwood]

So every item I have sold I have always had Eligable Seller Protection.

Now I have my biggest transaction of $1000+ and it says "Not Eligible".

This is making me very nervous. The buyer has a good 100% rating.

The only difference I can see is the buyer is using eCheck and I am waiting for it to clear.

Why is this happening?

Doug