How can I add AppleCare+ to my iPhone 16 Pro purchased from Amazon UAE while in Sri Lanka?

I purchased my 16 pro in april thro amazon UAE . Currently I’m in Sri Lanka for a 6 months and i setup this in Sri Lanka. The apple care + was available for some time and now it’s not able to add. I have no issue with send to apple UAE for warranty claim but now it’s not available how to get it back?

how can I add apple care +

[Re-Titled by Moderator]