iPhone screen dimming issue SOLVED!!!

I have had this problem on my phone for years where the screen will dim for no reason. A minute later sometimes it dims again, then again... then at some point it will pop back to full brightness. Auto-brightness is disabled. I have reset my phone, you name it. The problem follows me from phone to phone so it is software... last night I think I found the cause!!!  I like to use Siri when I am doing my astrophotography to wake me up to check my exposures as they come in. I will say “Hey Siri, wake me up in 30 min”. I will also use Siri this way during the day for different things, which has resulted in hundreds of alarms at totally random times in my alarm clock. About 200 inactive alarms or so, spanning all hours of the day. As the time would come for an alarm, even if it wasn’t active, the screen would dim on my phone! If another alarm was set for a minute later, it would dim again! It took several minutes to delete all the alarms, and when I did, the dimming problem has completely gone away. Hope this helps anyone who has been as frustrated as me.