I have just started a libre 2 sensor for the first time. I have set the alarm to go off when my BG drops below 4.5 and goes above 13.3. The alarm went off overnight and as a consequence I resolved the situation by taking the normal corrective measure. However my alarm is continuing to go off despite my BG readings being within my acceptable parameters. i. e. 12.2, 10.5 etc. Can anyone explain that please?