Reliance Communications — undue payment demand

I have paid all dues to reliance communications as per my last bill demand of ₹1304 which was thrice more than my average monthly phone bill. I paid the complete amount;thereafter they gave noc to my new service provider (Jio) to port my nbr clearly stating that i hv no outstanding bill pending with reliance communications. Now they are harassing me by sending bill for ₹708 for the month of january 2018. On december 31st 2017 i received a message from rcom stating that all my mobile records have been erased from their database;shockingly i am not able to understand how have they managed to raise a bill on my mobile nbr [protected] which was ported with jio network since 29th december 2017. I request you to kindly save me from this mental agony and harassment of illogical payment demands from my previous service provider as soon as possible.