Merchant irregularities - It took 6 months for a transaction I swiped for to be debited from my bank account

On the 23/11/2017 a transaction (I was unfami**** with) of R1000 took off on my FNB Cheque account from Edgars as a merchant. Disputed with the bank and received feedback today via sms to say, "the transaction was reserved on the 25/05/2017 and the merchant banked the transaction late on the 23/11/2017". How is this even acceptable?? I swipe for something on the 25/05/2017 for it to only take off 6 months later?? Both FNB and Edgars need to sort this mess out. Why should I suffer for their irregularities?? Why should they get away with this? Now I will never want to swipe at Edgars ever again if their banking is so poor!