No Response to emails after sale is made

I went out on quotes for tracking systems and tracker came out the cheaper. The admin and installation process was great. Everything went well during the sale process. The after sales process is pathetic though. I mailed my key account manager for my invoice on Sunday. I was promised feedback on Monday. I sent 2 subsequent emails on Tuesday and Wednesday...no response. Tracker is only interested in making a sale. The after sales service is bad. All i want is my invoice and the cost of transferring the unit to another vehicle...cheap is no good and good is no cheap...tracker you know where you fin in this!!! Definitely wont refer you to my friends and family...with this level of service i i should be at you competitors<br>