why I cant add esim to my iphone 11 pro max?

You should be able to unless the phone was originally sold in China, Hong Kong or Macao. What is the model number?

There are several reasons why you might not be able to add an eSIM to your iPhone 11 Pro Max:

1. Your carrier may not support eSIM: Not all carriers support eSIM, so you'll need to check with your carrier to see if they offer it.
2. Your iPhone may not support eSIM: The iPhone 11 Pro Max does support eSIM, but not all models do. If you have an older iPhone, it may not have the necessary hardware to support eSIM.
3. Your iOS version may be too old: eSIM support was introduced in iOS 12.1, so if your iPhone is running an older version of iOS, you'll need to update it before you can add an eSIM.
4. There may be a technical issue: There could be a technical issue with your iPhone that is preventing you from adding an eSIM. In this case, you may need to contact Apple support for assistance.

I hope this helps! If you have any other questions, don't hesitate to ask.

 eSIM on iPhone is not offered in China mainland. In Hong Kong and Macao,

Your phone may be locked to a different carrier than the eSIM is provisioned for.

What happens when you try?