Very bad service

Hi I am a very unhappy client, I order the milk special online @ Spar Birchgate in Kemptonpark on the 25 April at 11:19 order number 39710. I received an email on the 25 April at 16:30, to inform me that my order has been cancelled. With no explanation or refund confirmation. This is so unprofessional and when I called them they had such a lime excuse which I cant understand that apparently it happen to most off there client not even an apology. On top of this now I need to wait 7 days for a refund. I will never use Spar online again in my life. Very disappointed in there service.