Food Panda — worst customer service ever

I sent mail yesterday to customer service that i am not able to apply coupon quick or any other coupon which were sometime earlier i was able to apply but when i was going to order it was showing you do not have any coupon.

When i contacted customer care via mail, they said all coupons have been blocked in my account. I asked them why but they are not replying. I have sent several mails afterwards but they haven't replied on even one.

This is the worst customer service i have ever faced in my life.