The mini6 screen is yellow!

Let me ask you a question, why does the screen of the newly bought iPad Mini 6 feel yellow and red compared with the mobile phone? (It's okay from the front, but it will be more obvious if you look at it from the side) I still have this problem after the original color is turned off. I asked the customer service and said it was normal and there was a "warm and cold screen" Is this normal (I don't know how to make it directly display the picture QAQ) https://imgur.com/a/bPqpXwT