iPad brightness keeps changing despite automatic settings being turned off.

I have all automatic brightness settings turned off on my iPad, yet it still adjusts itself when the light in the room changes. It sometimes goes up so quickly it makes my eyes hurt, is there any way to make it stop? I bought the iPad brand new only about a week ago, do I need to return it? It’s driving me crazy ):

For example, this was it reacting to the light coming through the curtains: https://imgur.com/a/9iJApk5

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