No response from Sony Mobile

I have been in contact with Melissa Warren, a representative from Sony Mobile. She has been arranging a phone replacement for my damaged Sony Xperia Z1 Compact but has ignored all of my latest emails. The last time I got a response from Sony Mobile was 30 April (over 2 months ago!). I have sent numerous emails following Melissa's confirmation of a new phone being on its way. This is completely unacceptable! From the beginning I have had extremely poor service delivery in getting a replacement device (particularly when they refused to accept fault on account of their ***** warranty terms). I expect better from an international entity like this!