Why is my iPhone not eligible for AppleCare?

apple care+ is not a thing in all countries

Buy an AppleCare plan - Apple Support

and one needs to sign up for it within 60days of purchasing the device you wish covered

if this do not make it clear to you then you can try reaching out to apple directly

Apple Support

Just to clarify the 60 day eligibility period - it is 60 days from first (new) retail purchase from Apple or an Apple authorized seller. Buying a used device from a non-authorized seller often means the eligibility period will have passed.