Ucount rewards

I would like to cancel Standard bank Ucount rewards, not needed anymore and at times you as a client loses out, it's not the first time noticing that sometimes you would do as required to get a certain reward, but then it would simply come up as expired reward, meaning you didn't qualify, the most recent example I can make was with last month 'Spend R500 or more at any Caltex or Astron" I did that, the first transaction was R490 and the second on was done on the 31 May (you had up until June 2nd to make the purchase), for an amount of R574, but yet I didn't qualify, as mentioned this is not the first instance there have been lots, please cancel my ucount subscription