Paytm Mobile Solutions — unable to apply promo code

Address:	New Delhi, Delhi
Website:	paytm promocode section

I tried booking show for 7th june thu at m2k pitampura 4.40 pm.
But what i found is that i am unable to apply the promocode there.
Then i tried applying promocode in some other show timings it was applying there.
Then what i observed was the 4.40 pm show at m2k pitampura is only shown in paytm movies section
But not in bookmyshow site
And also on the same show timings i am unable to apply the promo code.
Kindly see to it