It's actually ~93 billion light years in diameter, you took the radius. But that's beside the point. The light traveling towards us is ~13 billion years old but the space this light had to cross to reach us is expanding at an ever increasing rate. Light is, logically, limited by the speed of light but space can do whatever the hell it wants. Hence, the seeming discrepancy.
Remember that lightyears are measurements of distance, not time :)