4 months still no Response

I have received the worst customer service from Sunglasses Hut, In August 2015 i sent in My D & G sunglasses for a repair which was covered under the warranty i was told the part needs to be ordered from Italy so they will rather send me a voucher and just assumed i will be ok with that, after i objected they said they will order the part and get back to me its been about 5 months and still no word from them. this is by far the worst customer service by any standard in the retail industry.