Cannot find which alarm to wake me up

I am using oneplus 6 with Android 10 in OxygenOS 10.3.3. In recent 2 days, I was waked up by the mobile alarm at exactly 08:30 am every morning. However, I cannot find the alarm app which generate this wake-up alarm. I have checked the recent app, there is no app running recently at around 08:30. I search my app with the keyword alarm, I found 2 app. I am sure that I does not set the wake up time in these 2 app at 08:30. Actually, I set the wake-up time to 07:10 for one of the 2 app. So, I feel quite strange. Where is the 08:30 wake-up time set ? Is my mobile hacked ? Can anyone help me to find out why there is an alarm at about 08:30 am ?