16-06-2020 7:40 AM - edited 16-06-2020 9:33 AM
Everything you need to know about selling on Ebay, incuding how to set up automatic bill payments, is in the Seller Centre (link at foot of any page).
If you are trying to pay for a purchase, does the seller ship to your Country, as unless the seller quotes postage to Sri Lanka you cannot pay.
I think that is what the confusing message you have received really means.
If this is the case then you need to contact the seller and ask for a revised invoice showing the correct postage.