Checking the sleep quality this morning, shows usage 6.4 hours and AHI 0.5 and the sleep report shows 2.3 hours and AHI 2.3 for 1 day and the same for 1week, 1month, 3month etc... Here we go - Aliens again
I unplugged the machine, taken the SD card out and made myself a cup of Ceylon tea. After a while plugged the machine, put the SD card back in the machine and let the machine read the card. Waited few minutes and everything is OK. The cup of tea done it