Worst service for new clients

I did an application on the 5th of October which was approved, on the 13th I was advised they dont have stock for the device I ordered. To my surprise on the 22nd I received another sms with a different reference number, I called on the 26th only to be advised that someone changed the device I ordered to a new one. Called today to be advised even the new one which I did not approve is out of stock. I was being transferred from pillar to post with no help. Please advise what must one do now.