I think it's just an oversight, but it's possible your country does not support the commonly used methods of online payment, such as PayPal. https://www.paypal.com/us/cgi-bin/webscr?cmd=_display-approved-signup-countries-outside
There are lots of other countries which are not listed or have a flag in UR.Like Bangladesh.I don't know whats the problem with the UR staffs to add the missing countries in the flag list. It won't do them any harm,rather would be great for their business.
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