Vodafone — I am unable to Port out my number to other operator

Myself Prakash Senapati, currently i am facing A problem on my “VI” Number which is [protected] and the problem is i am unable to Port out my number to other operator because whenever i tried to get the UPC code by Sending message PORT(Space) MOBILE NUMBER to 1900 but i didn't get the UPC Code. From their end i gotcha a quoted message “UPC cannot be generated as there are subsisting contractual obligations with your service provider. Please contact your service provider for further assistance”.
Please take a look and give me a solution regards my error.
Will be kind towards yourself for the rest of my life