Wifinitive Corporation — threatening to pay money before the submission day

This is about wifinitive corporation..
They asked me to pay the money before the submission day... And the as per the agreement it is stated that if you are fail to submmit the work on the submission day... You will get a 12 days chance after the day of submission to pay the registration amount which is rs 4500

But they are asking for the amount before the submission day.. And sending me legall notifactions..

Please somebody help