Hey, I assume you didn't completely cover the first patch with the second patch, but just patched over the edge of the first patch (with the second patch). I've never tried that before (I've never tried patch completely over another patch either). I guess I would have tried to completely remove the first patch and start again dealing with the original punture. That might not have been easy to do if the old patch (the part still attached to the tube) was really bonded to the tire. Anyway just goes to show that it's worth trying an idea out to see if it will work.