Cycling VO2 max not calculated

Hi all, I have a garmin forerunner 255 for my running activities and an edge 830 as secondary device for my cycling activities with a garmin power meter since few months. My watch is computing a running VO2 max since the beginning of my usage but for some reason, the edge 830 does not compute any cycling VO2 max while I use it almost every day with a chest HR monitor and power meter with some activities that goes well above 20 minutes with a HR >70% of my max HR. Any ideas ?