Those codes means there is an issue with the speed or ratio differential between the primary and secondary pulley, possibly the ratio control stepper motor. The ratio control piston tend to jam in the valvebody and this is part of the ratio control system. The 2nd code is low secondary pressure, also a potential solenoid issue. That 2nd code is not good. Main problem here is now these conditions will wreck the transmission. I'd say the valvebody is the culprit but also that it's now going to have done some potential damage internally to the CVT.
Not sure how it can drive good with those codes but clearing them and seeing if they return is one option. If the CVT isn't slipping, rpm surging/pulsing, or overheating then keep on driving it as normal. The speed ratio will be obvious and so you can check in manual mode the various expected speeds/rpms for each ratio position, especially as you shift up into the higher ratios this will become obvious if there is an issue it'll present itself. Datalogging using CVTz50 software will also confirm the actual ratio vs. commanded ratio is being achieved. This will also confirm any pulley slippage along with correct ratio control plus monitoring of CVT temps and ability to clear any DTC. A failing CVT will tend to show those obvious symptoms, datalogs will confirm it, and also throw DTC codes as well. That 145k mileage is up there for a CVT so I'd start saving some money for a CVT replacement regardless. When the time comes just buy a Nissan reman unit from the dealership as this is the least expensive and quickest solution to the problem. A dealership can confirm all this anyway if you don't have time to troubleshoot but you can also do it yourself.
