Body Care — non responsiveness from staff

I ordered a pair o[censored]ndergarments from them which they got wrong item delivered amd when i emailed them to exchange it with another item or refund me.. They are not replying me at all.. As they have self courier system so how can i know wht should i do now own.. As they are undergarments they have to be returened immediately otherwise they wont refund it.. Hope u will help me in getting my prob solved as soon as possible