I ordered something online on the 12th April and to this day never received the order

I ordered something online on the 12th April and to this day never received the order. I send 2 emails on the 29th April and 06 May querying were is my order. The courier company called and firstly I was told the driver can't locate the address. Secondly I was told they will investigate and revert. On the 16th I called their call center and they said they will investigate and revert. Now they're busy sending me reminders that my account is overdue. I send an email, the guy told me to pay as long as they are investigating. So the question is what am I paying for.