CVT Constant velocity transmission malfunction at higher outside temperatures

Goodday all! Mine is a Nissan primera 1999 model SR20 series. I've been driving the car, which I bought used, for about 10 months now. The car operates normally until recently. When in motion and outside temperature reads 30C and above, the cvt malfunctions: it will stop transmission and seem to remain only in one gear. When I stop the car and restart it the CVT light flashes 16 times, problem continues. If I park the car overnight and outside temperature reading drops below 30C the car resumes its normal operation, CVT transmission resumes with no problems, until again the higher temperature reads again. The temperature gauge meter (different from outside temperature sensor) remains and never crosses the middle of the gauge, so I'm not considering overheating. Pls what is actually wrong and how can I address this anomaly? I appreciate your help please.