Add new Data/Cellular plan missing in setting.

I set up eSim on my Iphone 11. It was working perfectly for 7-8 months. One day the phone fell down and all eSim data was wiped out automatically. I get another physical sim and try to convert it to eSim again. The Add new Data/Cellular plan missing in setting. I tried scanning the QR code directly through camera/QR scanner, however it says "Mobile Plan can't be set up; eSIM installation is unsupported on your device"

I tried searching on google but can't find any solution.

I find others also have this problem and unrelated solution is being replied to them. Kindly help on this matter.

My iOS version is 13.6.

My main query is "Where does this Add New Data Plan goes? Is it removed in iOS 13.6? If so how to scan the QR code and why doesn't scanning the quote directly from camera doesn't work?"

P.s. Kindly don't give this link https://support.apple.com/en-us/HT209171, please read the problem carefully, the above link is no way related to the problem.

Screenshot of Setting is attached below. I can't see any Add new data plan here.