Bharat Sanchar Nigam [BSNL] — Not providing any UPC number

Website:

bsnl official website

After sending several PORT messages since 2 days to 1900 for porting my existing BSNL sim to jio service provider; I am not getting any UPC number. A message stating "UPC cannot be generated as there are subsisting contractual obligations with your service provider" is sent to me whenever I send a porting message.
Even after contacting with the bsnl customer care, I didn't get any positive reply.