[BUG] Trade Depot Won't Export

Just like most of everyone else on this thread I too am having a similar or the same problem. My trade city was killing it with trade revenue at the start when it was just exporting ore. Then went up to smelting, and then it wasn't until I got started making and exporting the bug became apparent. My delivery and trade depot trucks would dissapear out of my city and never come back when they were full or empty regardless. I thought it may have been a traffic problem  and they were being held up in traffic outside the city, but no wasn't that. they were just leaving to never return. The only brief fix I tried was bulldozing all the delivery truck to my trade depots, mines and factories. Only for them to dissapear again in a few game hours.