Disgusting service regarding a customs clearance

I have never experienced such horrific service as I have from DHL, unfortunately I had no choice but to use this courier and the service I have received is nothing short of appalling, but rest assured I will never use them again. Firstly, my parcel arrived from the US a month and a half ago. The status read "customs clearance delay" for 20 days before I eventually phoned and asked about this. I was then told to provide bank statements and only 2 weeks later was given an import duty bill (can DHL also inform me how duties cost more than the good itself? Are taxes levied at 110% of the price?). How on earth was I supposed to know that I was supposed to phone? Could somebody at DHL not have phoned me or could the status message not have read "please contact DHL"? Then after phoning week in and week out for another 3 weeks, I was told the parcel would be delivered on the next day. It did not come. Then I was told it would definitely be delivered by the next week, it did not come. I was then told it would be delivered today, and when I phoned someone at DHL they said that now it will come next week. Also, the representative who has been "helping" me with the case has been horrific as well, not returning my calls, sending me the same generic email, not replying to my email. Can DHL please sort this out, before this becomes even more ridiculous.