Evetech not delivering

I have ordered and paid for two computers. Almost three weeks later the computers have not been delivered yet. I called, several times. Each time I am told that they will talk to the Dispatch Manager. I have been promised that the computers will be here by 2, then by 6, then on the next day before 3. This is unacceptable. The courier company used by Evetech is Aramex. I call, no answer. Several times. Evetech needs to use a different courier company.