Annoying Trying to book movie tickets but discount doesnt work!

For the past 3 times I tried to purchase movie tickets (always purchase 2 tickets) online for nu metro. when I get to the point where I want to add the discount, it accepts 1 then gives an error. and when I try to book the tickets again, it says, This loyalty cannot be app**** for this movie!! This is the 3rd time this is happening now and this too, I am booking tickets for Shazam which releases tomorrow only!!! I find this to be unacceptable as the previous times I ended up having to pay the full prices for the tickets!! I demand that this be resolved and I get to use my multiply to receive the discount for the movie which I want to watch on Sunday at Emperors Palace @ 17h15!!