Nissan Repair Questions? Ask a Mechanic for Answers ASAP
It looks like you are experiencing the transmission failure that is typical of these vehicles. Fortunately this transmission is covered under an extended warranty. If you are under 120k miles and 10 years the transmission will be covered under a factory warranty.
That being said, if the only code you are seeing is a p1778 (p0710 just indicates that the transmission detected a fault-nothing specific) it might just go away unless it is an active code. I would probably still take it to Nissan and have them address the transmission under the extended warranty if it still applies to your milage.
Please let me know if you need additional info.